Hi LAT,
I'm not sure if someone in another thread has recommended Splitting: Protecting Yourself While Divorcing a BPD/NPD Spouse by Bill Eddy. Even if the laws are different in your country, the approach that Eddy describes (and the behaviors to be aware of) is very helpful.
The US family law court system is adversarial by legacy, so a lot of us find ourselves being pitted against former spouses, even though courts here seem to forget they perpetuate the very thing they tell parents to stop doing
I wouldn't invest too much time trying to get the therapy records from 10 years ago. A lot of courts prefer things that are more recent, unless things work different in your country. Can you file a motion for a custody evaluation? If so, that might shine some light on the behaviors you want the courts to see.
If you have reason to think that your wife might file false allegations, that means she is (in Bill Eddy's words) a high-conflict personality (HCP). Someone who is HCP will have a target (you), recruit negative advocates, and be a persuasive blamer, in addition to having some kind of PD. Eddy also describes three levels of BPD difficulty:
*generally cooperative, not dangerous
*not cooperative, not dangerous
*not cooperative, dangerous
For the last one, dangerous includes false allegations of child molestation or domestic violence that lead to legal abuse.
If you are dealing with that last one, then definitely plan your exit carefully. Take a lot of time, be three steps ahead, and create a boatload of documentation. Prepare yourself for false allegations by keeping a binder filled with receipts in case you have to counter (with documentation) her claims about your whereabouts, even if it is to poke holes in her credibility. Find out from your lawyer if you can record someone without their consent. In the US, those laws differ state by state. Keep a journal, or track what you're doing in a Google calendar (you can print this out as an agenda with everything in chronological order). Photocopy all important documents and store them somewhere safe.
My ex was a former trial attorney and threatened all the time that no court would take my side given his knowledge of the law. It took four years, but I ended up with full custody, thanks to friends here and a good lawyer. Some of it is sheer luck of the draw, like who you get as a judge, and good your lawyer is. All you can do (and it's a lot) is to plan carefully and learn everything you can.
Divorce is very emotional for both partners, whether BPD or not. The more information you gather, the more you plan a safe exit, the better the chances you will come through the storm with your boat intact. She will likely dysregulate no matter what, and that can be scary and also raise eyebrows for people who are assigned to your case.
Work this forum over for help

It's a great place to get feedback and advice on figuring out your goal, your strategy, and tactics to help keep you and your kids safe, including your wife, who will probably do all kinds of things to make things worse for herself.