Does it really even have to be a person? Could it be that the team was finding a way to lose most of the time, and players were getting down, but once they pretty much knew how the season would end, they started having more fun playing instead of watching the standings? Maybe having catchers drop like flies seemed like bad luck.
Heck, maybe it is partly some of the players they still have: CJ down because the opposition figured him out, Wallace not liking his hitting instruction and sharing his frustrations, or Towles with an attitude, Meyers frustrated with himself, or a combination of all of the above, feeding the whole mood.
Bringing in some kids that were having good seasons and enthusistic about their quick rise in the ranks had to have changed the overall mood, even if the end result will still be pretty much the same.
