Do you know if Android Settings' factory reset wipe the TWRP backup folder too? I want the TWRP folder deleted from internal storage too, and hoping the factory reset did it.

I can't boot the phone now, and don't want anyone in the future to access TWRP Nandroid backups. How do I check if it's there?

Also, if someone gets my Nandroid backup, can they restore it and access data without knowing the unlock pattern/code? What if they knew the pattern/code?