Wow. IF this were me - I couldn't do it
BUT....please don't base your decision on potty training issues. I Agree with Livingdustmops - think about what's best for HIM.
The training issues should not be the reason you decide to rehome him. If you think he's going to spend all his time
alone then I would base your decision on how much time is actually going to be spent with him. Yorkies are very social dogs. If you think you can offer him the attention he deserves - then I would def try to take him.