Alina could be Alan for all we know...
The assumption that if something is organised by a woman it must be OK but if it's a man is must be dodgy is one we need to knock on the head right away. Sex/gender has nothing to do with it whatsoever.
I am not sure I can get what you mean? We do have ladies?
In English, 'girl' is the word for a female child, not an adult woman. It's sometimes used colloquially to refer to female adults, but plenty of women object to being infantilised in this way, and obviously when we're discussing prostitution it's probably best to keep words that refer to children out of it altogether.
Please post the name of your establisbment on the thread, since.your link apparently isn't available until your website is back up.