Although D9 has been in therapy for a few months already, uBPDw has been asking lately to have her generally evaluated by a psychologist or psychiatrist (most recently expressing that she suspects D9 suffers from DMDD).
I understand your hesitation to see this as all positive. uBPDw is open to therapy for D9, but may also project things onto D9, and perhaps rush her toward medication.
There are people, both with and without BPD, who might be inclined to medicalize stuff that could be rooted in family dynamics.
Trying to tease out the correct diagnosis during pre-teens can be really tricky. My son went through 7 different diagnoses before receiving one that finally makes sense. Not that the earlier ones didn't apply, only that there was one in particular that kind of explained all the others.
You have a moving target because D9 is so young, and it's hard to know how your partner will respond to decision-making if she royally dysregulates during and after the divorce. Meanwhile, D9's care would be compromised.
Sometimes parenting orders focus on short-term things, as well as long term. I had a similar dynamic to yours and a big chunk of our temporary order was focused on then S9's psychoeducational evaluation and subsequent ADHD/ADD dx.
You could use the temp order process to do a trial run and see how uBPDw handles the shared decision-making. If it goes sideways in a big way, and you can document that, then the permanent order is where you would say Hey, wait a sec, this is what has to happen so that D9s care is handled properly.
That's roughly what happened in my case, except my ex was much more high conflict than it sounds like your wife is.
We basically made an attempt to perform joint decision-making on the court's clock, and I was able to demonstrate that ex was more focused on obstructing simple decisions than getting S9 the evaluations and care that he needed.
Whatever you do, have a plan for what you'll do if you end up in obstruction alley
