I would talk to him again, keep it light, have a sense of humour, and apologise for being so intense last time. Explain that you want to work on this together, that you love him to bits, that you find him hot as hell.
Don't focus on the problem. Focus on making him FEEL good.
Ask him what he needs from you. Don't fill in words or bombard him with suggestions. Just ask him what HE needs, sit, be quiet, wait, and listen.
I totally understand where you are coming from and how you feel. It's really, really difficult dealing with things like this, because all you want is to figure out what's wrong and fix it - and also not be the only one making an effort.
But it sounds to me like he's embarrassed, and feeling all of the weight of responsibility for what he probably sees as a sex life failure on his shoulders. This is why it's important to keep it light and playful and flirty between you, rather than heavy and problematic. At least for now. If you're a year down the line and he's refusing to engage, that's a different story. But at this early point, you don't want to cause him to close off by making him feel like he's under a microscope. You know what I mean?