Changes can Alter Appetites
I had 2 dogs and 1 died randomly so my other dog stopped eating and got really skinny for a while, then about a month later my grandad had an idea that Moochie was just lonely, so we got him another playmate, he liked the new dog at first but after about a week he was sick of sharing his toys and food with her, so just so she couldnt get the food he would gorge himself beyond walking!! so maybe your dog is just not liking the new changes being presented to him so fast, give him time and dont punish him, this is his way of dealing with himself right now, ITS HARD FOR THEM TOO!!!