Don't know if Allen is the answer.

Health to the major players is Vegas' key to competing in the Pacific. Manninen is a wild card that could payoff.

Allen will give us much better goaltending as a backup or a 1B to LT than Brossiot will. Plus both are on expiring deals and Allen will be just for a season

Not much point in the trade for MTL. They get a worse goalie, at a time when the have next to no stability in net, and the save less than a league minimum contract in cap space while only getting a 3rd rounder.

Both are on expiring deals and Allen's health is hwta lets his value down for Vegas

Doesn't explain how this deal makes sense for MTL. They gain almost no cap space, and with Price going on LTIR they don't really need any so the difference in cap has almost no value. They downgrade in net which is a position they are already weak at, and even in a rebuild having alright goaltending to keep blowouts to a minimum is valuable. MTL has so many prospects right now that they will need to let a large number walk, so another 3rd round pick doesn't have the value it would have to a team with a thin prospect pool.

Allen stays put in Montreal for now.
Price out for season