Well (as I read it, maybe I misunderstood something), the TVs in question worked (in HD as far as watching shows go) as well. It was just the same issue you're having (PS3 wouldn't display HD, but worked in SD). That's why I figured it might work. Certainly couldn't hurt, could it?
And other than hard/factory resets, it's the only thing I've turned up. Maybe CM's vid will help though.