The union is in a tough position. In the most pejorative sense critics will ask is the union worried that future players who enjoy choking women unconscious will receive even longer suspensions? It's tough to find a path in to protect players from potential career ending suspensions without defending their actions. In this case someone who enjoys choking people unconscious.
I think the two years makes more sense as a starting point for negotiations than what MLB believes will work.
Perhaps the union can make a statement that based on the CBA, union guidelines, etc they are required to offer the following assistance as they have with other players. We do not condone the behavior but etc etc etc
The real possibility is he accidentally kills someone. Could you image this M Lol B presser? Hey we knew this guys gets off choking women unconscious, we thought he knew what he was doing, but he got a little carried away and this one died. We are confident it was consensual and the grand jury will not be pursuing charges.