Do you have a way to tow or truck it home? I'd demand the bike back. A head gasket should take two days, not two months. With just 1500 miles on the bike, you shouldn't even have to mill the head.
I would also contact Triumph USA and demand some sort of compensation for being without a bike for so long.
I would also contact Triumph USA and demand some sort of compensation for being without a bike for so long.