While I'm aware theater is on the second floor, I see nothing but stairs to get up in the photos, and just wanted to make sure there's some other sort of way to get up there as my mother can barely walk. Is there an elevator or escalator upstairs?

They're 3 sets of elevators close to the parking levels. They're very fast to get you up there. Also theater is on the 3rd floor. The 2nd is the box office(it's closed) buy the tickets at guest services in the main entrance or online with QR code for speedy entry.

They have both.. But elavator is riht next to main entrance

There are elevators available