[gemy]

I'm going to chime in here and make some suggestions. Yes this is serious, and probably has been building for some time. I've recently been reminded, that sometimes you just have to train some things over again.

So set up for success I agree with. First for this scenario work one on one with your male yorkie. No other dogs or ppl there.

Have two bones = value treats. Give one bone to him. Let him settle in - but not in his crate. Close off crate or bed areas etc. Create the environment for success.
Now say his name ask him to come - if he doesn't 0 bring out the other bone - proffer it to him with the come command. He should come hopefully and be willing to exhange his "bone" with the new Juicy bone. Praise him highly for this.

Let him chew new bone for 10 - 15 minutes. Take old bone ie first bone; grate some parmesan cheese over it. Call him again. Proffer "new old bone". Praise him well if he comes and takes new bone.

This is enough for day one.