I'd love for him to come down to my office while I work but he just
won't come, he seems scared. I don't want to force him down here. I
did manage to coax him once, maybe I'll try again.
I suggest you take him there on a leash in a very no-nonsense manner, close
the door so he can't escape, then give him a treat and a toy or yummy chew
and let him get accustomed to being there while you work.
I have a very spooky rescue dog, and she would never learn to be anywhere in
the house but the kitchen if I didn't take her there on a leash or kennel
lead. Coaxing has no effect other than to heighten her fears. She's becoming
more and more comfortable around the house using the method above.