The difference is that here I use SCP, and for Windows I used SFTP. That is because even after generating the keys with PuTTYgen I could not figure out how to “install” them into PuTTY to use a command pscp -scp (the PuTTY scp) in the Command Prompt. That and the fact that my teammate was more comfortable with GUIs, so I picked the first thing that worked.
upd. I forgot to include the most important line in the Nginx config. Sorry for that. but it does not work for me anymore. I am confused but I am postponing this for a few days to finish top priority tasks.