Are there any other words you use where "rot"is used as a sort of pseudo prefix?

I don' think so. I believe rotgut is a simple compound word, of the form V + N, along the lines of pickpocket and cutthroat. It's interesting how some words get a life of their own as Dutch rot.

band name

Yes, I think it would, too.

Ceci n'est pas un seing.