They were longlining, so I'm not exactly sure how they got these squid--usually when fishermen catch giant squid, it's because they come up in trawl nets.
The fishers didn't bring any samples back, unfortunately, but the rupture in the squid's mantle did leak an important piece of information: this squid was a female. That big white thing spilling out is probably a nidamental gland, an organ that makes jelly to wrap around and protect eggs. (Gender ID initially made by Angel Guerra.)
Also, for anyone who's upset over that poor squid sloshing around the deck, rest assured, it is VERY dead.