After dealing with the drowners bug and successfully giving the black pearl to Nidas, he doesn't show up at the Golden Sturgeon, so I can't collect my reward or complete the quest. Has anybody had the same problem? Thank you.

Weird. I've done that contract twice and he always showed up, both on older patch and the latest patch. the bug I'm experiencing with the latest patch right now is the inn keeps are sometimes missing then when I tried meditating suddenly they're back.

The only thing I can think of is to meditate for 1 hour. Since day one i've had an issue where some of the armorers or blacksmiths in Novigrad won't be at their shops. If I meditate they've always appeared after wards.

I hope it works for you because this quest, despite its brevity, has a very good ending.

It's possible that he was killed after you gave him the pearl.

It's a rare occurrence, but there are situations in the game where even quest givers are killed - by random monsters in the world.

In my second playthrough I played a quest for Hans the mercenary and while I was walking towards him, a wolf jumped and killed him. Right in front of my eyes. It happened so fast, I couldn't do anything. Luckily I had another savegame that was only 10 minutes back, so I hurried and reached him before he was killed - which actually happened again, but this time only after I had already turned in and thus successfully finished the quest.
He was never killed in my first playthrough. Random crazy stuff can happen in this game.

Some people can never complete the gwent quest, because someone holding a card is killed on his way back to the village. It's random if he crosses monsters on his way to the village or not.

Turns out Nidas was back in Skellige fighting the drowners...again. He gave me the reward right there. Thanks for the help.

And i can't save him from drowners. i just can't swim so fast.....