2015 Ford Explorer - Knuckle issues

Ford Explorer Rear Suspension Issues:
Hello, I have a 2015 Ford Explorer with 152,000 miles. I bought it brand
new and travel a lot to construction job sites throughout the state. I have
always kept up with oil changes and scheduled maintenance. The dealer I
bought it at in Green Bay had an excellent maintenance department and
other than rotors and under-sized OEM brake pads I’ve had no troubles.
Then we move to Madison and it is a different Ford dealership.
In August of 2019 Ford recalled the rear suspension toe link which was
labeled Repair # 19S17 and covered it under warranty.
During the recall work the dealer’s mechanic (Madison dealer) said I
needed extra work to be done (not covered under the recall) – a
replacement of the upper control arm bushing - $551.98 and also replace
rear brake pads and rotors - $489.03. I had him perform the extra work.
This week, when I went in for my scheduled oil change & systems check,
the dealer mechanic recommended replacing both rear knuckles –
estimated at $1,580. The mechanic didn’t actually talk to me, he relayed
the message to the service desk person. I didn’t have time to talk to the
mechanic, however, when I asked for more information, I was told: “Well,
cars are expensive to repair, etc.”
I realize I now am entering higher mileage and more repair or preventive
work will start to be needed but I miss my other mechanic who is 150 miles
Questions: How do I know if I really need the knuckles replaced?
Wouldn’t the “rear knuckles” have been replaced with the rear
suspension repair of August 2019? If not, why not?
How many miles do knuckles typically last?
How often does something like a knuckle need replacing?
What are some worst-case scenarios that could happen if I wait
to replace these knuckles?
What can I do to calm my wife down about driving on
“borrowed” time with questionable knuckles?
Any direction you can provide would be appreciated!

Get a second opinion from an independent mechanic. Ask friends, family, and neighbors for recommendations.

I think the mechanic really meant rear bearings, not knuckles. At 152K miles that would not be unreasonable. As for the cost, the bearings run about $140 each and a lot of stuff needs to come off to replace them.

Also, the rear knuckles have 4 bushings in them that may also need replacing. It may be less labor (and cost) to replace the entire knuckle than the 4 individual bushings.

But the dealer should have been able to explain all of that.

And no, these would not have been replaced with the recall.