Agoraphobia induced diarrhea...please help!!

My small company is moving in a few weeks and one of my employees does not think he'll be able to make the move with us.
Here is the situation:

He lives just 2 blocks away from work now. He lives at home with his mother and rarely leaves this 2 block area. I now know why he has always been resistant when I try to send him on an errand which requires him to go anywhere.
He explained that whenever he has to go anywhere, i.e. the store, doctor, etc...he tends to get attacks of diarrhea. It is especially bad if he's going into an unfamiliar situation.
Now I don't know if this is Agoraphobia, but it sounds like it to me.
He used to play golf and go on fishing trips, but would load up on Immodium to get through those, and now since his father passed away a few years ago, he's been unable to do any of those things.

He has to build himself up to go anywhere at all, and he's doubting he's going to be ready to move to our location which would be a 25 minute drive for him.
I've offered to pay for some sessions with a counselor that I've seen, but he is down right scared of the "head doctors" as he calls them. I cannot convince him that getting some help would greatly increase the quality of his life, not to mention his job security.

I really don't want to lose this guy as he's been with me for 10 years. He's a valuable member of this family and it would be a shame.

Any advice would be helpful.

The problems brought on by his fear of needing the toilet is problably leading him to become agrophobic as hes trying to avoid the situation. If the problems are physical or not he should still see a doctor about it, they may be able to advise him on a new diet or if its fear bringing it on, he may find Diazipam helpful. I would suggest Cognitive therapy for him, Ive tried several programs, and seen many people but this has been the most effective decision for me. Hope this helps!