There might be some confusion over the use of "foundation" here. I'm using it as in the cement foundation for the building itself. The yeti is on an elevated platform structure, which you can't see unless you're behind the scenes. This structure, the mountain/building structure, and the roller coaster structure are all independent of each other in that they don't touch, but they do all share the same giant building foundation. There are footers for the roller coaster supports and yeti platform supports but they are all within the giant foundation for the whole mountain.
Anyways, the rumors that there are giant cracks in the foundation are false. Whatever was being damaged is something only the engineers know for sure.