I went through something very similar here in NC. After 42 years, and as the original owner, I was able to do a bare frame no money spared restoration/upgrades on my 7.73 850 Commando. Towards the end of the project ( I thought, more on that another time), I decided to get the paperwork sorted. I went to DMV (great down here) and presented a clean NY title, NY insurance cards and registration. The woman ran my VIN and said my numbers came up as stolen. She said someone could have had "fat fingers" typing in the numbers at some point. She said she was sure the info was incorrect, but I had to contact the NC Agency that handles this stuff, which I did.
An agent came here to my shop to take pics, inspect the matching numbers on the bike, my original title, insurance and registration cards, NY tag, receipts and pics from back in the day, etc. and said he was also confident I was the owner and he would help me to get a NC title. Interesting is that once he filed his report, I was able to get NC insurance, tag and registration so I could put it on the road. The DMV lady said it could take a year to get a title, but the great agent said 3-6 months even though I paid for it already. It's been about 6 months now and I plan on contacting him for a follow up.
He explained the system to me. Back in the day, before the federal program, and given the small amount of numbers used for VIN's, that sometimes the same VIN would be on different vehicles. He said my VIN was also related to a middle '60's Porsche and some American Car of the same vintage. He said in Ford's case, they might throw a letter like a "F" combined with the numbers for a VIN. When the feds took over, the confusion with the older vehicles started. So part of his investigation in my case was trying to track down any DMV or Insurance records on the other vehicles over many years. He quickly determined in 2 days that basically those vehicles no longer existed "in any system" and that he would push to get my title through. I only really cared because when I check out, I want my much younger wife to be able to sell all of my toys and other assets for tax free cash.
He said that he's found a lot of bikes through insurance records. In one case, a guy in CT bought a new Harley in the early 70's, and within a week it was stolen prior to him generating any paperwork and the follow up to find the bike was fruitless by the owner. He refiled a claim just a few years ago and my agent, through insurance records, found the completely restored bike in a Harley dealer, and the dealer had to give the bike back to the original owner with zero compensation.
I'm not so sure that my issue can help you, in my case I lucked out with a cool agent who was very knowledgeable and enthusiastic for people to have their restored vehicles on the road, include muscle cars from back in the day. You seem to have plenty of documentation but maybe try getting a different agent or insurance records to back your case. The dealer would have had to have it listed on an insurance policy (you would think) while he owned it.
Good luck with this and if I think of any other guidance I can give you after I contact my agent, I'll gladly pass it along.......
