Regarding that provision in the law about passing. Yes it looks like your sister may have committed a moving violation by passing on the right.
However, the other driver committed what appears to be me to be a much bigger violation by then crashing into your sister’s car and running her off the road. Her moving violation does not absolve him of responsibility for causing the crash. Even before the crash, he was also committing a moving violation by driving on the wrong side of the road.
I also haven’t heard anything about the other driver having an immediate need to move back into the right lane. There isn’t any mention of a semi-truck coming around the corner the other direction leaving the other driver no choice.
The video is important. Without it, the police do not believe your sister’s story and they might her entirely at fault. If that happens, it could have serious consequences for her insurance. She might even lose her license for reckless driving. Maybe even face criminal charges.
It also sounds like the other driver gave a much different story about what happened to the police than your sister. If the stories matched, the police would not have disbelieved her. It’s probably better to show the video to police to bolster her credibility and destroy the credibility of the other party. The police already know about the video and are expecting it.
If your sister sues the other driver for damages, the court would be in a position of determining who is at fault. Fault in these types of cases isn’t all-or-nothing. The court could decide your sister is 10% at fault for trying to pass, but the other driver is 90% at fault for ramming her and causing a crash. The result would be a win for your sister as she would likely still get a considerable damage award.
A judge or jury could even decide your sister’s passing on the right was not a cause of the crash. After all, the other driver rammed your sister when nothing forced him to do so. If he wanted to return to the correct lane, he could just have pressed the brakes and then moved behind her. In that case, a court would probably find him 100% at fault.
It is good advice for your sister to contact her insurance company immediately. Doing so might be required under the terms of her insurance. They also have their own attorneys and can advise her on what to do next.
Given that your sister may have committed a moving violation at the time of the crash, it is also good advice to consult with a criminal defense attorney immediately. Just in case.
Regarding a restraining order: If your sister wants a restraining order, she can apply for a Civil Harassment Restraining Order in the civil division of the Superior Court. If the police or DA presses charges against the other driver, the criminal court might issue its own restraining order (Emergency Protective Order).