In Borderlands 3’s new DLC, the new Call of the Deep quest has a glitch where if you die as Omen is saying he’s gonna pull out Fish Brother, the quest glitches, Omen never pulls out the fish, and you are unable to continue, leaving the Watch Fish Brother Make Entrance objective unchecked forever. Saving and quitting does not work in my experience, and neither does restarting the game.
Solution/Edit: I’m still awaiting a response from 2K Support from the ticket I submitted to bring this issue to 2K’s attention, but I was able to find a solution thanks to the comments on this post that worked. Fast travel from Skittermaw Basin to the Lodge, fast travel back to Skittermaw Basin, WALK all the way to the objective marker, and Omen should reel the fish back up. Credit goes to @jchturnbull. If anyone is still having this glitch/issue despite this solution, make sure to post it here to let me and others to know and to also submit a request to 2K Support on their website.