I don't think any of the circus shows, including Cirque du Soleil, run under Equity contracts. The work terms are completely different. That's not saying that they shouldn't be protected by a union (which is what Equity is for--it doesn't necessarily define the calibre of a production), but it's probably very difficult to negotiate that kind of a contract.
I do feel that Jungle Fantasy is a poor rip off of Varekai, but if the audiences like it, then fine.
"Peace! The charm's wound up."
--Macbeth