The middleweight Charles was a little green still quality but not the finished article like he was at light heavy. I think Ezzard would still win but a hard earned decision.
If a prime Robinson Lost & had his hands full in other bouts with LaMotta. A Pre-Prime Charles will not beat LaMotta. Although a LightHeavyweight fight would be entirelly for Charles. A Middleweight fight would be for LaMotta in a bruising fight. LaMotta UD.