Maybe the seller want's to private his personality. Its good for you both to hire a trusted escrow just to make sure you're money will not lose. But I see no reason why the seller doesn't wan't to show up his face it turns me up to curiosity.
If it smells like a scam, I'd spend not 1 more second thinking about that deal and I'd look somewhere else.
Escrow "offers" were used in so many scams, I'd never buy anything unless it's from a reputable store, or paid on arrival.
I think large shipping companies offer this option, why wouldn't the seller use it if he's legit?
Or why wouldn't it be ok to go there and get it in person? For a 40k deal I'd fly over.
Many scammers are veteran in doing that we should be aware of. Face to face dealing is the best option you could do. You can assure with it. If you are not sure about that think twice or thrice so many legit sellers that could offer you more to trade safety. Unlike that one its very suspicious.