Mays will be on the team for this season. All $4m is guaranteed right, so why cut the guy if you still have to pay him? And no other team is going to trade for him unless the Broncos eat a significant portion of his contract. So basically he is back to where he was when he played for the Eagles, a backup MLBer.
I think the Broncos just really like Mays and wanted to give him a shot at being the starting MLB but they now realize he's just too much of a one dimensional player. Perhaps Fox thought that Del Rio could get more out of him or something? Maybe Del Rio just really liked Mays and wanted to see if he could be the guy, who knows? That being said the Broncos are really in a curious situation at LBer as Williams is AWOL/WTF?, Mays is benched, Miller is basically on the LOS all the time, Woodyard is ok but can't cover in space, Trevathan is a rookie, Brooking is older than dirt, and Irving is still an unknown. It's simply wierd that the Broncos didn't make LBer more of a priority on the off season.
The Broncos either need to have 4 guys on the LOS that can get consistent pressure on the QB so it frees up Miller to play more of a traditional SLB position, or they need to make LBer a priority in the offseason. I'd prefer they do both but we shall see. Heck, the secondary still needs work too.