If Fel Moonglow docks are shut off from the city, it's something specific to your shard. If it's a problem at sea, I didn't look, because the 15-20 year old water elemental infestation of that bay makes me never use its docks. Note that if you're doing the High Seas fish quests, you just have to have your ship on the same subserver as the city, and that you can recall to Moonglow from a ship parked at the Floating Emporium to deliver a Moonglow quest, or park at Jhelom, Skara or Trinsic, and be able to deliver to all three of those cities without moving.
You do not get double fish in Fel, though you can get some rare fish that are facet specific.