My theory (discussed elsewhere) is that Talgo would lease back one or more of the Oregon trainsets, since they are under-utilized at the moment, and will be so until more slots become available in the Cascades corridor in 2017.
The problem with that theory is that the Oregon Talgo trainsets have 288 seats versus 397 seats for the Wisconsin Talgos. WI did order 3 spare Talgo cars, but those were a cab car, bistro car and end coach/bicycle car (19 seats), so there are not enough spare cars to cut into an Oregon trainset to match the WI capacity (unless there are spare coach cars in the NW that can be leased for 3 years).
My guess is that if MI leases the 2 trainsets, they will designate 2 of the daily Wolverines as the ones with the new shiny equipment "HSR preview" trains while the third train remains a Horizon train. Or maybe MI wants to add a daily frequency rather than wait 3 years for enough corridor bi-levels to become available. Looking forward to see how this plays out. The Talgos may be at Beech Grove for a while, but in the meantime saving Talgo a bundle on monthly lease payments in WI.
While the move will be at night, hopefully someone will be able to get a video of the doubled up trainset on the move.