I myself have a similar issue. I have used 7zip and I attempted to extract the patcher. But my issue is when the patcher does not show up as a .exe file. It shows up as an application. This is with the most recent downgrade patcher for 3.0.0
I tried to extract the whole thing inside the SPTARKOV folder I copied and pasted the game with. But I did not get the results that is supposed to happen. So I tried to do the methods both shown in the video version and written version, but I could not get a patcher.exe file.