I think he never really got back on track after Tompkins died. The Aldo fight had something to do with it too, but less than the impact that death had on his training, IMO.
The Aldo fight is very overrated, it was a great display of toughness and heart but for four rounds it was far from a "fight" he only got that shining moment because Aldo gassed from the beating he put on him. Hominick simply was not on his level.
I have no idea what will happen in this fight, Homninick, skill wise is so much better but if Garza lands something big I think he'll put him away.