Could you arrange to have a few good friends stop by on occasion and practice the behaviour with him?
My last yorkie had a collapsing trachea, and when she was young I had friends, neighbors & my kids friends stop by to help train her to stay calm. It took about a month of solidly working with her. She'd still bark and run to the door to acknowledge someone, but she wouldn't get worked up over it and end up gasping for air.
__________________ (Chelsea  ) |