If you turn up in costume, no photography allowed at all. If you are just there in casual wear, I don't see any issues with photography within. If you change into costume inside and take photos inside without their permission, they'll call the ranger and fine you on the spot. LOL
Katy is one of my favourite cosplayer too. She's sexy, creative and smart. She knows how to pose for the cameras, suggests great ideas and also very much involved till the end product you see here. I would definitely love to work with her again.