We have parking in Annex Park where the festival is held?
There is also parking on the street next to the park.

Yes. Right next to the ticket gate. The park is handicap accessible via a gravel pathway.

You may be able to park on the street next to the park, but the best place is in front of the arena. This is public city parking and accessible from the highway. It is less than five minutes walking to the festival grounds from there.