Oh greenlotus, I can feel your frustration from here, and just wanted to let you know that someone heard you!
Now, here I am going to speak as someone who hasn't had the nerve to do what I am suggesting - but I think you really have most of what you need: clear instructions from the psych, and general agreement from the principal that those instructions would be followed. Perhaps if the teacher is not available to meet, you can cheerfully assume that it is because she is happy to move forward and doesn't need to again discuss the specifics in the short term?
It sounds like you are personally prepared to drive (feed them) many of the accommodations anyways, so could you just do it? Act like she's totally on board and aligned with everyone else. E-mail the teacher (daily if need be), copied to the principal, saying essentially, "as we discussed and has been elaborated in letter from psych, today we are sending DD in with the following alternative materials to work on. She has been signed up for course x, and we will work with the school admin to ensure that within 24 hours she has on-line access during class time. We are happy to come in on the following dates to work with the whole class on z. We are really looking forward to talking with you at the Nov meet-the-teacher about the effectiveness of these approaches, and what additional steps we can take to ensure DD's educational success this year."
OK, I admit, I speak with no experience. It's just what I wish I'd do under the circumstances, and hope I'll do if we get to a similar place. Hang in there! It will get better. The principal is on board, the 504 is coming, and you are obviously fully equipped to make it happen, with or without the teacher. You're doing great!
