Thanks for all the thoughtful replies, guys. A little more context: this guy dances/strips in several local gay bars. None of the bars in my state allow for private lap dances or private shows, but after the strippers perform they come out and "mingle" in the crowd for tips. Depending on how much you tip them, they will push the boundaries accordingly, though the furthest I've ever seen them go is allow you to grope them inside their underwear. It's all rather tame, but it is what it is considering our prudish laws.
I am encouraged by all of the comments indicating that I'm not wildly off track for even considering asking him. In one of the bars, I had previously asked if he did "private one on ones". My intent was to find out if he was willing to meet me privately outside the club, but I guess I wasn't direct enough because he responded that the club didn't have a space for that. But then he said, rather cryptically, something to the effect of "But we can make that happen sometime for sure." He then went on to talk about the possibility of getting couches in the bar to allow for something more private. So I'm not sure he really understood what it was I was asking.
I think I like the wording, "Do you ever meet guys privately outside the club?" To me, there's no ambiguity what I'm asking. The worst he could say is no, right?