The last play was a result of the Ed Hochuli call earlier this season. The refs let the players finish the play, and if they were wrong, they'd get the call from upstairs to go under the hood. That call never came.
I can accept that forcing the on-field referee to personally review the call would have been a tidier ending for everyone. However, what you and others cannot accept is that there is a logical reason that the "call never came" from upstairs.
EVERY play in the final two minutes of each half is reviewed by the booth official, and the booth official contacts the referee when there is any question that the call on the field is correct. So the booth official's judgment was that the fumble call was clearly correct. Please understand that it does not always require 12 replays to determine that a call is correct or not. If the first replay the booth official sees confirms the call, then that is the end of the review process.