Thank you for that background information. That helps my understanding of what would have otherwise been a very curious and puzzling name.
BTW, the restaurant still exists, serving hearty German fare. It is both popular with the locals and with tourists. Whether it still is a gay meeting place, I cannot say, however, but probably not. They serve everybody who is hungry, though :-)
I would expect that people would not talk about it's past history. I am told Germany has some very strict anti-Nazi laws and no freedom of speech as exists here in the US.
On your last paragraph: yes, and yes again.
All the best for you, as I‘m finally getting off this site for good. See my profile page (as long as it will still be there) for more :-)