Additional thought: see if an independent mechanic can locate and install a functioning used transmission (maybe from a lower mileage wreck) at a better price. Then dump it with a clean conscience.
Consider Consumer Reports reliability ratings when selecting your next ride.
Also, are you certain this problem is the beginning of the end or is there a possibility it’s something less serious?
Please do not think that I am being combative as I do not mean it that way. You mention that I seem to be ignoring a large number of complaints. The question would be number of complaints vs number produced and of that number of complaints how many were due to lack of service?
The transmissions are manufactured by JATCO which is roughly 75% owned by Nissan. JATCO also produces CVTs for countless other car makers.
One would be hard pressed to believe that the main owner Nissan would build junk for their own vehicles but no one else.
You mention the car having regular services and fluid changes. That comment does not answer the question as to whether the CVT fluid was changed or not. If so, you should have records and if not available the fluid changing dealer should have them.
Every manufacturer has their own specs for the transmission. I’m not sure that the Nissan spec is the same as the other customer’s specs are.
The idea of a steel belt running on cone shaped steel pullies seems like a bad idea, especially on a heavy high powered car. Sure the rubber belt design works ok on low powered scooters and even snow machines but the belts are wear items and easy to replace. How some companies manage to make them last the life of the car baffles me.
I bought a new Nissan in 2018 with a manual transmission after doing my research on the terrible JATCO CVTs.
IMHO, offering a 12-month warranty on a transmission is the opposite of standing behind their product. It’s typical for products like this to last far beyond the warranty period, so a high number of failures barely out of warranty is grounds for criticism. I think the same applies to the appliance that needed repair after 15 months.
Along those lines, I’d say a company that hides behind “we’ve done all that was legally required” when a design flaw comes to light is deserving of criticism.
I agree with that sentiment, and I don’t like that things don’t last as long as I think they should. But we can argue all day long about what should happen. The fact is we have to deal with what does happen, and what is normal.
The definition of “normal” is typical, usual, or expected. If every third car on the road uses a quart of oil every 1500 miles, that is now expected, or normal. Home appliances used to last 20 years, now they don’t. That is now normal.
We bought new top of the line Maytag laundry machines, the washer needed a new circuit board after 15 months. We bought a new Samsung gas range, the oven needed a new igniter at 4 years. We bought a new top of the line Kitchen Aid refrigerator, one of the control panels went bad after 3 years. Is it normal to need to repair your appliances after only a few years? It is at my house.
Amazing that they last as long as they do! Something has to wear on a cvt due to the nature of the belt / pulley contact, either the belt or the pulley sheaves or both. The less torque required, the less wear. I used cvt’s on industrial machinery, but they were placed so that just removing a cover exposed the belt and pulleys for quick easy replacement.
I agree; I was just commenting on the “standing behind their products” comment. Most cars now are better than ever, but unfortunately the CVT-equipped Nissans are an exception.
The mistake you made was buying top-of-the-line appliances. Although this sounds counterintuitive, the cheaper, more basic appliances have fewer problems, and last longer than the higher-end models. For example, a basic refrigerator with the freezer on top and no ice maker or water dispenser is likely to last much longer than a fancy side-by-side fridge with through-the-door ice and water. A basic top-load washing machine is likely to last much longer than a fancy front-loader. And so on.
As a former appliance repair man I agree. Simple is better. The bottom end Kenmore (Whirlpool) washer I bought in 1988 is still working fine.
All water under the bridge at this point, but the repeated question of whether that CVT was ever serviced in 105k miles remains unanswered.
A cut and paste below from an Infiniti dealer…
Automatic Transmission Flush (@ 30,000 and 60,000 miles)
It was answered. The vehicle had all scheduled service completed, at the dealer, including 4 transmission fluid flushes.
Nah man, we can’t do anything cheap or simple at my house. 
My wife is in charge of buying appliances, and she’s the biggest techno-junkie there is. We have a fridge that has mood lighting with a water dispenser that will measure out 12oz of water at a time, a washing machine that has wi-fi, a dryer with a steam option. She also has a car that will parallel park by itself. I suppose you could say that I’m her “enabler” because I make it possible for her to have all these things by fixing everything at much less cost than the average consumer!
On the other hand, I believe in buying quality and having it last. I buy Snap On tools because they have served me far better than other brands. I have a stereo receiver (one of several) that cost $600 back in 1978, and costs significantly more than that now.
I can honestly say I don’t understand why a washing machine needs wi-fi to clean your clothes, but then again I suppose some people don’t understand why you need a stereo receiver that costs $1000 just to listen to some records.
I suppose the difference for me is that I understand the higher cost of ownership that comes with a high-end car/washer/stereo and I don’t complain about it. But the world is full of BMW/Lexus/Benz drivers who think that $100 for an oil change is a rip-off. They should be driving Chevy Cruzes.
Happy wife, Happy life. 
If mama ain’t happy, ain’t nobody happy!
Myself I would never buy a Nissan or Infinity CVT or any CVT for that matter .
Love those old Pioneers, I am still using the Pioneer SX-727 my father bought around 1972 ( I think ).
At 137,000 miles my 2014 Mazda6 developed a known transmission issue affecting the first 8,000 cars built that year. I was well out of warranty but Mazda Corporate sent a brand new unit (redesigned so it would not have the same issue) and split the cost three ways between me, the dealer, and corporate. The whole job, including new front control arms set me back $1,500. Based on how Mazda handled the situation I am a Mazda customer for life.
Good customer service makes a difference. Not many car companies replace a 137,000 mile transmission with a brand new unit, but Mazda did.
something tells me Nissan has an opposite math - all units but last 8,000 per generation might not have the problem… 
This is what I was hoping for with Nissan. Some consideration. Ironically, since I have sold the Infiniti in question a couple days ago, my wife has us looking at Mazda (CX-5, CX-9). It’s her car, I’ve never owned Mazda. But your post does give me encouragement.