FWIW, I agree. It certainly went higher than I was prepared to pay for it. Had I known it was repaired, my max bid would have been lower still.
The seller clearly knows more than they were initially letting on given they've had the wherewithall to know what possible frame failure looks like, and find a specialist welder to fix it.
It is plausible there was never a problem though as paint is notoriously bad at sticking to titanium - and I can tell imagine normal stresses producing frame failure like appearance. I have some painted titanium forks, and there's one place where you could actually peel the paint off like nail varnish if you had a mind to.