Trade that was preposed: Team A L.Hernandez + FA#5 for Team B Lawrence + FA#1.
To me, looking at the trade as is, there should be no reason why it shouldn't have gone through. Team A is rebuilding already having 4 1st round rookie picks AND having no FA picks past the 5th round. Team B is defending leaugue champs and wants to stay that way.
There MIGHT be a reason, though, if you delve deeper into the 2 teams rosters. Team A ace is Hernandez and after the trade it would either be Lawrence or Penny which the commish might think would weaken the team too much. But who knows, the trade didn't go through and now it's way to late to worry about it.