If you’re playing devil’s advocate then they’re not your words, you are advocating for the worst version of an argument. So why would it be a problem for be to mention satan? Unless those are actually your views, in which case you aren’t playing devil’s advocate.
You didn’t deny the holocaust, but your argument is flawed. The nazis thought of the Jewish people as a race. They attempted a genocide on that basis. They were being racist. Proudly so.