I don't know where it was posted or where the information came from... but somebody sid that the rumored cost was 17 mil.
Also. These corporations DON'T just build these coaster on faith, they build them KNOWING that the concept WILL work.
What I have heard is that companies in the business of coaster building first look around at the assortment of coasters companies out there, for certain products they offer and also inquire over new products in development.
I think, Busch looked at Intamin, Mack, Premier, Vekoma, Gerstlauer, and maybe some smaller companies like Zierer who had dabbled in LIM launch technology. They proposed the idea of a multi-launch coaster with dark ride elements and the moving track section. Companies like Intamin and Premier have had experience in technologies like these.... but Zierer may had provided the lowest price over Intamin. It's not like Intamin said no... but were just outbid by Zierer.
Just my speculation.