this may not be feasible, but can you just swallow the damage and move on? is it worth it to let go of the bike when you can replace the fork hopefully inexpensively?

I know you've already spent your money, but most of the bike is there. You've spent weeks already scoping it out and found what you want. Maybe the next one you buy will cost you more anyways, so why not keep what you've got, replace the fork, and if they say they can't honour it for insurance anymore, then maybe you just have to factor that in as the overall cost of the bike? Who knows, they MAY still honour it. I'd say if they give you flack, maybe take them to small claims? seems odd that they would want to fork out money for shipping it three times across the country.

Sometimes you end up paying more to have what you already have... sucks, I know, but sometimes that's the best option.

Hope things work out!