Trying to unskew polls is never a good idea. That being said, I'd be utterly shocked if Vance lost this race, though it almost seems like he's TRYING to lose it.
I'm not as certain. We've seen several polls in a row with Ryan ahead, and not all of them have been internals. In fact, if this is a John Bolton PAC, this would basically be a Vance internal.
Ryan would probably win if the election were held today.
There hasn't been a independent poll of Ohio since late May (which shown Vance leading).. so yes, they've all been internals.