How can I hire a lead diver in a single-player game? I have never seen him in the list of recruitable NPCs, the only way I found is to spawn him through the console.

Sadly you can't do that. You'd have to make a submod for that which overrides outposts making it incompatible woth outpost mods

When I take the diving goodies perk, the console gives me an error code, haven’t taken the perk since but I don’t believe it gave me the items after I completed a mission.

Crying Seals Talent doesn't unlock hammerhead harpoon.

(From 'Ammo and Explosives) Large Titanium Hammerhead Grenade

(From 'Talents') Large Titanium Hammerhead Harpoon

Also, the 'Talents' item name is different than the (un)craftable item name in 'Ammo and Explosives'.

I hope you see this and get a chance to update it. I really love this job.

Thank you for all your hard work!

When unlocking some of the talents such as seadogspirit and thick blood i get errors such as Could not find the characterability, or unable to create an ability for the skill, or Trying to add null ability for talent. I don't know what the errors mean. I'm assuming that these talents just don't work.