Ask them.
I've went on dates with guys I've met from Tinder, Grindr, through friends, at a gay bar & in a gay club. All you need to do is start chatting (or if you're in the club, maybe other things will happen first

). If they're not interested, just move on.
There's nothing to lose. I met the guy I'm seeing just now through Grindr, so miracles do happen on that app.