Number one and number two
Such undignified names for cats, that really can't help the bonding process! Seriously! It's like they have no identities to you yet. How can you expect to bond with a cat who shares a name with poo poo?
Also, as Sherry said, why are they under a couch in a busy room if they are so afraid? You are not doing them any favors by doing that, and that will likely prolong the time it takes for your scare-dy cat to feel comfortable. Also, be careful with the whole eye-contact thing. Holding eye contact with a cat is actually a hostile act. It's seen as a challenge. It's what a cat does to another cat right before he launches a vicious attack.
My one other comment is: what does it really matter how much time it takes your timid kitty? Is there a deadline? Lets say it takes a month, two months? three months? six months? I mean you could potentially have him for 15-20 years. Whatever time it takes him, it's kind of small potatoes in the bigger scheme of things, so I wouldn't be so concerned over that.
One more: I think the visit to your vet probably told you more about the vet than the cat (you already knew your cat was not yet well acclimated to people, and a vet office is arguably the most stressful situation possible for a cat). If a vet doesn't have a good rapport with both myself and my cats, that's a good signal to look for another vet. It sounds to me like not only was he insensitive, but also handled the visit poorly. I'd dump him.