Thanks for reporting this and providing the extra details!
I've looked into it, and it seems very likely to be a false positive. (Maybe it got flagged because of the adult content?)
As long as you downloaded RCD directly from my itch page and haven't installed any unofficial patchs or files from other sources, there shouldn't be any reason to suspect that your copy has been tampered with.
I totally understand why that warning would be concerning, though, and I really appreciate you bringing it to my attention!
