To be honest, the only manufacturer we can properly rule out at this stage is Togo!
It could be anybody. Who's to say B&M haven't been working with AT on another new concept. B&M have never done anything such as trick track, and haven't introduced a new ride type since Air in 2002. In fact, B&M have never done anything other than coasters with a good old fashioned lift hill (excluding Hulk, but then the launch wasn't done by B&M). Times have changed, so maybe B&M have decided its time to do the same!
I'm not saying it is B&M, as I still have my money on Vekoma. But then again it could be intamin, mack, Gerstlaur, Premier, Maurer...