Where did you read that? It was a steel casting with 6" wall thickness. In any event, cyanoacrylate glue was not widely available 60 years ago. As a class of adhesives, cyanoacrylates are classified as having "weak" resistance to moisture, making their use to fabricate submarine parts questionable at best.
Regards,
GtG
History channel, has a show about it same as discovery, after they glued it and tested it they rigged a metal strap around it to keep the two halves in alignment. Maybe be available on computer try a search. I saw it years ago.