TC, I feel a sense of deja vu, reading your post. I hear you telling yourself that you're fine, you're not falling for this guy's lines, you're just being friends, yadayada.
But whom are you trying to convince? It sounds to me like you are trying to massage this relationship into something that will end up being OK for you. There are red flags all over the place--hooking him up with your therapist? Whatever spin you put on it, I see you getting sucked into something that will wind up with you hurt. Even the fact that you are talking "boundaries" and how long it might hypothetically take for him to be relationship material suggests you are wading right in.
You are CO-WORKERS. If he doesn't even have your number, why are you hurting your head over someone so clearly unavailable in every conceivable way? Why not spend your energy and time with people who will enhance your life rather than suck it dry?