First of all, this promotion is not in the past, it's still up and running starting yesterday and ending some time Sunday. Anyway, it's annoying this happened, yet it's not a scam per se.
First of all, your whole approach is kind of off. Chasing a level up with guaranteed losses is such a low value action, that's exactly what the site wants. And when a casino wants you to do it, it's bad for you and good for them.
Even when you get the bonus finally they just pay you with your losses. It's always much smarter to achieve a level up organically. 1.2x is also such a bad promotion itself as well, in their ANN thread I even wrote nobody (even super low levels) would be even remotely interested in such a bad promotion, obviously I was wrong. 

By the way, the money you lost up until the point when you realized it didn't work would have been lost no matter what, I mean you basically wagered to lose anyway, so there is no refund necessary. The only thing that's missing in your account is 20k in VIP progress, and that's really the only thing.