Hi Mulberry, so sorry you needed to join us here. It's really the best place, though, for information and support to help make your way through this hellish journey.
Although it is maddening (and scary) that no one can give us a roadmap for our family, it's true that we each have to find our own way. One of the few "good things" about this vile illness is that we do know what needs to happen - food is your d's medicine, and she needs enough of it to get back to a healthy weight, meaning, whatever weight is healthy for HER. Getting her there, though, is the hardest thing you will ever do. And however hard it is for you, it is much, much harder for her. Ugh.
Hard as it may be to believe, many here (raises hand) have initially found "professional help" that was much worse than you are describing. It is great (!!!) that your team expects you to refeed your d. I'm among the many who were told not to. (Unbelievable, I know, but true.) So please try to have an open mind about them.
It's whatever works. In the Torie Family, that included a lot of bribery, what felt like superhuman patience, and watching like a hawk for years. "As soon as you have finished your breakfast, you can go to school (or watch that show, or phone a friend, or whatever is motivating at the moment)." I think we all have found hidden food at some point, in spite of feeling like we are supervising closely - it's like this illness turns them into magicians at disappearing food in the blink of an eye.
Another thing that helped us was to say, "Here's your meal; you need to eat this," and when her reply was that she couldn't, I would tell her that my job was to help her eat, and if I couldn't do a good enough job of that, I would need to take her where the experts could do a better job helping her. I wonder if it would help for you to say something similar, but end with, "or we will need to let your dad be the one who help you with this meal."
At times, spoon feeding her like a baby helped. (Yes, she was a teenager.)
Separating my d from the illness helped. By that, I mean keeping in mind that my d wasn't acting like this as a choice or because of a character defect - she was being impossible because her brain had been hijacked by an illness that was trying to kill her.
So here is my advice:
Watch her like a hawk. If she has the opportunity to slip bites into her pocket, up her sleeve, to the dog ... she will.
Keep her with you for at least an hour after every meal. The LAST thing you want is for her to start purging. (Before the meal starts, ask her to use the restroom so she will be able to stay with you after.)
Remember that however hard this is for you, it is a hundredfold worse for your d.
Come here often to ask questions or just to vent. We've all been there.
Watch this video by forum member Eva Musby - it was a huge help to me:
Hang in there, and please be sure to keep us posted. xx