Also, as far as I know, nothing else on my PC has disappeared. Maybe I should contact Itch support?
I know it's been a while, but I did try scanning my pc again with the antivirus a while ago and afterwards the game stopped deleting itself.
I only remembered to say something because I was looking at the software the other day and found like 20 copies of The Chef's Shift and Typefarmer in the software's "Virus Vault".
Just thought you should know.