Nope, it's not a sellout but as far as I know only a few hundred nosebleed seats in the endzones are left.
The gold tickets would be good quality seats on the sidelines. If these are being offered, I imagine that these must be resold seats (scalpers), or being offered as part of a package.
There should be over 20,000 people at the game in any event.
I'm going to be there anyway.