Did you solve this issue?
I'm having the same issue and spent 1 hour with Turbotax tech support. They couldn't resolve this issue. I had the same problem last year and had to submit my Quebec taxes in paper. I will move to some other tax software else next year.
I bought again this year the standard online turbo tax to file for 2020, and I am having the same issue not being able to netfile my Quebec return because of duplicates empty forms for the TP-64.3-V form. so again I had to mail it. this is crazy!!!!!!