It worked out for us, but it seems there is a need for some training and a consistent policy. We made it to rope drop yesterday and were the first in line for the fairies, not realizing it was just for Tink and Fawn and that we'd have to come back later for Rosetta and Vidia. While waiting we saw a family approach from the exit and saw they had a GAC. After DD met the fairies I asked the CM if we could come back later through the exit to see Rosetta. I showed her the GAC, which does allow us to use alternate entrance when available. She looked at it and said, "No, that entrance is only for Make A Wish and for autism. I told her DD has autism. She looked at me with disbelief. DD uses a special needs stroller because of her many health issues and fatigue, but autism is her diagnosis. Because of the stroller, which really does look like a wheelchair, people tend to assume she has mobility issues and it doesn't occur to them that there are other needs.
They did let us come back through the exit. We waited right outside the exit for the same amount of time that we would have waited in the regular line. As DD's condition improves, I think it's important for her to learn to wait, and she is doing well with this. It's just the noise and jostling in lines that she can't tolerate at this point.
I was disturbed by the assertion that the alternative entrance was designated for a particular diagnosis, rather than on need. If that's how the CM has been trained, then maybe we all should be bringing doctor's notes after all. I encountered some misinformation as well. While we were getting our tickets activated, the CM saw DD and told us we could get a pass to bypass the lines. Yes, this came right from a CM. There is definitely a need for more training in this area.