It would seem it had to be structural if they were unable to seal the case. But I *think* you raise a question whether the case could have been damaged in service. As a watch person I'd love to have been able to talk to the watchmaker/tech who was involved, out of curiousity, but that's not possible, so we will never know what they were doing all that time. Perhaps trying to locate where they stashed the spare inventory back in 1997...