We are at Disney now. DD has PTSD and anxiety, and qualified for a DAS. It has worked well for the most part, but crowds were lower so LL queues were shorter. Some things that helped her: Remembering that she is familiar with the queue and knows about how long it should take helped her to reinforce that it won't take that long, you can do it. She also wore her earplugs, which she says help a lot, especially in queues like Buzz. The DAS let her enter via LL, and when she got to the entry way she would simply tell the CM that she has a DAS for anxiety, being enclosed in rooms with many people will trigger her anxiety, and asked if there any way she could skip the pre-show. This did and didn't work, and I've been in contact with area coordinators and "higher-up" people. All assured me that there are cut-throughs to help with this kind of thing, but not all CMs on the floor know about this. For sure we know you can skip the pre-show at Haunted Mansion, Tower of Terror, Rock-n-Roller Coaster, Dinosaur (be insistent here, they CAN read you the safety disclaimer and not insist you do the pre-show... but that's not how it went this morning and one of the reasons we lost about 3 hours to a panic attack), Mickey and Minnie's Runaway Railway, Star Tours. On the Safari, when we were about to board the vehicle, DD explained that the front row wouldn't work for her and they seated us in the 3rd row. You should also be able to go in the "back entrance" for attractions that aren't mobility-accessible (like Big Thunder Mountain). I also know from first-hand experience that they SHOULD be able to let you sit on the end of the front row of benches (well, on the first step, not ground level) at Festival of the Lion King (although that's not how it happened today so DD walked out but I stayed to see the show- at her insistence).
I wish we'd had some of this information before doing Disney this time around. It was really a nightmare at RnRC as well as today at AK (Dinosaur and Lion King). As you know, panic attacks can't be stopped by flipping a switch, and the after-affects last longer than just the amount of time it takes to stop the attack. I am pretty angry about the last 2 days we had, which is why I'm sharing so much here. Hope this helps someone.