If you are doing something that is a good cause, you should take money wherever you can get it without any ethical concerns. I would much rather have the MIT media lab to have that money than Jeffrey Epstein.
The only thing to watch out for is to make sure you are not rehabilitating an evil person's reputation. But if it donation is made anonymously or quietly, it should be okay.
https://en.wikipedia.org/wiki/Pecunia_non_olet