Hi left him at the memory den but I maxed out my companion affection with piper now I want to run around with nick. I thought he'd be at the detective agency but I can't find him. Console commands to summon him aren't working(unless I'm doing those wrong). I hope he's not dead. What should I do? I checked all my settlements too.

Probably Sanctuary. Companions patrol around

It appears according to the bugs part of his wiki page on Fallout wiki he may have vanished from the game entirely. Which really svcks. I don't know what commands I'd have to put in to get him back either I'm not very savvy with code.