Maybe, maybe not. New CVT is $2100-$2300. Installed easily $4000-$4500. He got quotes already, buying used is his risk. Without an inspection and datalogging, all speculation at this point. If I had that transmission on my bench I could tell you exactly it's condition and what would fail or is failing. In a garage, I could do the same by datalogging it and dropping the valvebody. Since I don't, the OP is trying it to a certain extent, the same as a Nissan tech would. I forgot to mention the CVT deterioration counts that are captured, that's another thing to look at to see the high temp exposure time.