HI Express was cleared with the Candlewood. Originally they were both going to be across Ft. Riley from Famous Daves. They did some ground tests or whatever and the rock underneath would be expensive as crap to build on so they moved the Candlewood across from the Convention Center (which the convention center was pissed about). Candlewood is extended stay and could've done a lot better with Ft Riley business in the original location. I hear its struggling a bit and that may delay the HI (same ownership).
Also, doubt Marriott would run the new hotel or SPG unless it is ran by the same people that own the current brand properties in town. Usually when you open the first or a brand in the area, you buy the rights to the brand in the area. So Fairfield/Courtyard owners could create hell for any other Marriott brand coming into MHK.
I hope they build the hotel. I think it is risky but could work if the area expands/NBAF brings in an absurd amount of people. Public transit would be a big help, though I'm sure they would have to do free shuttles to campus.