can i bring a folding wagon for my stuff so i dont have to carry it into the venue?

Honestly depends on who does your security check. There is conflicting info all over the place. Nothing on the site mentions clear bags, says soft sided coolers, but mentioned when you get the reminder email about your event. I had to swap a grocery bag with 2 items in it for a clear poly bag, yet I saw backpacks and regular coolers everywhere. So who knows about wagons.

I saw lots of foldable wagons being used in the venue, so I don't think it's a problem. I would take a look at the venues do's and do not list which should be posted on the venue site. You could also call the venue to confirm to be on the safe side.

No. There are signs all over the place that say no wagons.

That depends upon who sold you your tickets. You ask them.