Surprise: You Don't Have Car Insurance!

Last week I was in a car crash. I rear-ended another car on the freeway, my airbags deployed, the other car/driver had no visible damage (their car was much bigger than mine).

I'm insured and registered in Texas, but the accident happened in North Carolina

When I called my insurance to make a claim, they informed me that my last payment had been declined and I was no longer insured with them

The payment really was declined, 4 months ago, and it was probably my fault. However, if they had reached out to let me know, I would obviously have just corrected the payment info and paid the bill. They never emailed me, called me, or texted me (I can prove this). I can't say whether they sent notice by regular mail, since my mailing address was out-of-date. The people I've spoken to on the phone assure me that their policy would be to text, call, and email me before terminating my coverage, so obviously something went wrong on their end.

Even if I were covered, I only had liability coverage, and I assume I'll be deemed fully at fault, so they wouldn't be paying anything significant for my car. It's the other driver's costs that are at issue.

Right now, there's a claim from the other driver (I don't know any details), and there's my wrecked car sitting in a tow lot wracking up fees.

I know this is gonna be expensive for me, and I made some mistakes.

My question is, does the fact that they failed to notify me according to their policies give me any chance of having my coverage retroactively reinstated? If that's worth pursuing, what should I do in the meantime?

Also, I need to get the car out of the tow lot asap. (No, I can't store it on my property.) I have a buyer lined up, through Wheelzy. Is there anything I need to do before selling the car for salvage? Like an inspection of some kind?

Miscellaneous additional info: * I got through the paperwork at the scene of the crash before knowing about the issues, so the police and other driver have my "old" insurance info * The tow lot is reluctanct to give me access to the car before I pay the fees and remove it. I assume I can make them let a mechanic inspect it if need be, but the tow lot may be uncooperative * It's a big national insurance agency. So far I've spoken to some people in my agent's office (who basically think I'm lying), the lead agent won't be in till Monday. I also spoke to the claims adjuster who seems helpful and sympathetic