Free: Contests & Raffles.
that damage doesn't look like a typical seizure at all. it's hard to tell exactly what happened with the cylinder still on the case, but it looks to me like something got into the engine that shouldn't have. it doesn't bear the marks of a seizure due to heat or lean mixture at all, since the piston in the exhaust port is pristine looking, and you've got scoring on the intake side. a "normal" burnt up piston would be totally fried on the exhaust side. perhaps a bearing let go or some foreign material got in through the carb?i would absolutely seek a second opinion, sounds like the shop doesn't know what they're talking about.