My DH was very much like yours, it sounds (I'm also planning for a UC in September). I made him watch The Business of Being Born, Orgasmic Birth, Birth in America, and if I can find it, we will be watching the DHC Freebirthing documentary (what I love about that one is that all of the mommies successfully have UC with no complications). He is not much of a reader. I've also hired a doula who technically thinks we will be transferring (b/c she can't attend a planned UC, even though she seems to understand that that is what's happening), and the appointments we have had with her have been very reassuring for him. If possible, find a woman who's had a hb or uc who's dh would be willing to talk to him about the experience. There are also done great articles about hb and uc from a dads perspective on the website drmomma (peaceful parenting).
I also live a few minutes drive from the closest ER, and with my sister driving, we made it on 2 minutes flat. Practice gettingg there, my dh loves that

I have a coworker who also works l&d, who told me I need to be able to get to an ER in 6 minutes in the event of an emergency, you will probably find that you arrive in PLENTY of time!
Good luck!