That is pretty much old news. BNSF came to an agreement with Amtrak and the states of Colorado and New Mexico that if the states and Amtrak would fund capital improvements on the line (Raton and Glorietta subs), such as CWR and replacing signals, BNSF would continue to maintain it. The capital improvements reduce maintenance costs. Anderson tried to weasel out of it even after Amtrak got grants for it, but Amtrak ultimately came through.
BNSF track and signal gangs are working on the improvements on the line right now and have been for the last couple of years.
The line is now in no immediate danger.
At much higher risk is the CZ route west of Grand Junction, which has kind of flown under the radar. UP runs no through freights at all there, the only traffic is the CZ and one BNSF trackage rights train. Traffic is light enough that PTC is not required and is not implemented there. I think the only reason why UP is keeping it is that per the UP-SP merger conditions, if they abandon/embargo it, BNSF would get its rights transferred to the Overland Route and UP really doesn't want that.