While many women who go to strip clubs or book time with a dominatrix may be doing it to please a (male) partner, or as a learning experience or a lark, or just to make a statement of some sort, it would be pretty silly for a sex worker to be surprised when a customer, male or female, appears to be interested in having some sort of sex with her.
Your dancer granted you access. Maybe she liked you (or likes girls in general) or maybe she was milking you for tips, but whatever, she said yes. She has a sense of how sturdy or flimsy a barrier her G-string presents to curious fingers and was probably not surprised when you got where you got. The most telling thing was that she invited you back whenever, which she was certainly under no obligation to do. I think it would be fine to go back there and fine to whisper, "Sorry I got fresh last time" and fine not to. It would also be fine for her, in turn, to refuse you service, but I bet she doesn't.