[Toymeister]

Contractually speaking, they made an offer and you accepted it. There is no doubt that you signed an agreement that you would pay what the insurance did not. The agreement was in the initial paperwork that most people do not read.

I know this sounds harsh, I'm only posting this to point out that you have no small claims case.

Basis of comment, four decades of contracting experience (writing contracts). To comment that you have a case with some regulatory agency is simply a demonstration of the Dunning Kruger Effect.