Just a quick comment as yet another dog lover--so, the dog's situation is this? He can go to a shelter or rescue and go thru a rough time temporarily before finding a "forever" home that loves and wants him, where he will have a good life, or he can stay w/someone who will clearly not ever make him a priority or give him the care and love he deserves.
Hmm, does that sound more than a little familiar to any of us humans? The difference being the dog can't choose for himself. I would agree w/those who say to find a shelter or rescue organization that can find a new and better home for the dog, sounds safest and best overall to me.
Just my 2 cents' worth. Wishing you strength in dealing w/all that is going on.