Moving the gear stick is like moving through peanut butter, molasses, high viscosity

Hey everyone. So I took it to a mechanic. And I want to know what you guys think about his diagnosis.
He said the problem is the actual shifter assembly. The part that is in the cabin… He said it has nothing to do with the engine getting hot. It’s from the friction of shifting. But his reasoning for this deduction are a little strange. And he talked around my question of, once the car got hot and hard to shift I popped off the shift cable from the tranny, and it moved without issue. The thing that was hard to move was the shift block (not sure if that’s what it’s called) the cast iron piece that goes into the tranny. Before I got the engine hot I pulled the shift camel off and tried moving it and it was noticably easier to move than after it got hot.
That’s the main reason I disagree with the mechanics diagnosis issues that weekend I remove the shift cable from the shift Bock. That makes the actual shifter, in the cabin, completely disconnected from the tranny. It had 0 influence on the tranny, yet the shit block was very hard to move. So I don’t know if I’m missing something and this mechanic is right on the money. I really really hope he’s right and I’m wrong because the shifter assembly is $50 and super easy to install! Hahaha

If it’s so easy than you can change it. Or pay mechanic to do it? Will mechanic refund your money if it does not fix issue?

I talked to the mechanic today, he has been out of the shop over the holiday. I told him all my observations and how when I disconnected the shift cable the shifter moved freely even though it did not for him. He just sort of talked about other things. But I asked him if they do the work and it does not fix it will I have to pay. He said no. So I am just gonna have him do the work. I don’t think its gonna do the trick, but I really don’t know what else to do. I have talked to so many mechanic friends (all out of state) and they can not figure it out. So whatever, I’m just gonna pay the shop.

The mechanic is probably telling you that b/c that’s what the problem usually is with those symptoms on this vehicle, based on his prior experience. If that’s not what it is, just ask him to let you know before proceeding further. OP’s experiments do seem to point to the problem being inside the transmission, which is certainly a possibility. But it’s hard to tell via an internet description of how hard it appears to be to move things, and the mechanic may actually be correct on his first guess. I think my first guess above was the same as the mechanic’s.