As a person who ended up in a kerfluffle over some things said to coworker friends, offsite, at a casual non-work event, I understand whereof you speak. Howeve

As a person who ended up in a kerfluffle over some things said to coworker friends, offsite, at a casual non-work event, I understand whereof you speak. However, the instant it's on site, talking to HR about it is the right thing to do. They will give advice about the situation as well as document that you raised the issue. It's largely a CYA move in that you're assertively defending yourself against claims listing you among the group of people engaged in dumbass behavior. You can also anonymize the source of the humor. HR doesn't care about you, the joker, or even gay people. HR cares about protecting the company. They'll send an email proscribing such tomfoolery and consider the issue resolved.