Oh! This sounds very useful. We often dance in situations where the audience is everywhere!
So, essentially, when the lead is stolen, the troupe is changing the direction they face while they dance?

I personally don't like the term "stealing" the lead because it sounds like someone is showgirling the leader out of the way. Its not like that at all. It's communicating and adding to the conversation.

So, if the audience is in the round, of course discussions should be had on where your front is and/or if you want to present to several sides so that everyone gets some front focus. There can be any number of ways to change leads in that sort of situation. You can focus on flipping from front to back positions if you are in stagger setup. Or as a trio diagonal or duet, you can do the same by flipping from one end lead to the other end lead. You can also circle around when you want to switch and reset as a stagger in a different position.

As far as a follower taking the lead, that only happens when there is clear communication and sightlines so that each dancer sees that another follower is changing the movement and taking the lead. This happens during a half turn or pivoting movement (not during full turns, either fast or slow) so that people get a chance to catch the lead change - assuming that you are keeping an eye on each other. You have to be alert and anticipate it, even if it's not something that you would normally do, it is still an option.