Whew. I'm glad to hear she "snapped out" of the little pattern that seemed to be developing. I'd have been very concerned too, given her history. Any time we saw things like that in difficult child 1, where he was no longer interested in doing something that normally would light him up, it was a big red flag that depression was back.
I'm with you on the whole reward thing. At this age and even her level of development, verbal strokes really should be enough for the basic stuff and natural consequences, no matter how stubborn the difficult child, will eventually win out. in my opinion.
difficult child 1 used to run off, threaten to kill himself, say he would be better off dead, destroy things, not bathe, not change his clothes, refuse to cooperate, start fights for the pure stimulatory aspect, etc. I could tell, though, that it was mostly for show and mostly an issue of power underneath the mental health garbage, which just made it all a lot stickier.
I don't know how regularly you're able to get her to take medications, but if she's not, that could be a huge help and perhaps a motivator for her to get some of her privileges back that she wants so badly. The ol' do-to-get deal which I'm sure you know all too well. And maybe you've tried that already. To me, medications are even more important than getting the kid to go to school or brush their teeth or not drop an f bomb. Because I can't even get my kid to think about doing those other things if he's not stable. Please tell me to STHU if I'm way off base here (I have not been around much in a while or kept up on where everyone's at). What I've had to deal with has been microscopic compared to the scale of chaos you're facing and I don't mean to preach. I hope things settle down and you find some help soon.