I emailed them back, linked them to this thread and asked if they were sure there was nothing they could do. They said that it would have to be registered as a Bar-B-Kettle instead of a Statesman. To me, that was obvious, but oh well.
I am just glad it got registered. They even marked it down with a purchase date in 1968! They also said that they made a note on my account that it is actually a Statesman. Good enough for me.