I have been helmet shopping when I can looking for some big ass helmets and its becoming a pain. Right now I have a HJC CL-15 XXXL, while its not a bad helmets it does fog up and good ventilation is something that it lacks. The problem is that most places to not stock 3XL helmets so its nearly imposable to find out which ones fit. Which helmet manufacturers make large helmets?

Most manufacturers make large helmets. The troubl is finding a store that carries them in stick, so that you can try one on.
Is your head really that big, or are you buying a loose fitting helmet? The helmet should be tight to your head, including cheeks. When you try to pull it off, it should try to take your head with it.
That way, when you wreck, and your head flies off, the EMTs will be able to just look for the helmet.

Bun-Bun my head is that big, I went to a lot of places and tried on a few 3XL helmets the shoei 3XL cant pass my ears lol. My HJC is tight but I can live with it, I even tried some modular helmets but they hit my chin and cant close all that way. Its a real pain, I want a sweet lid but it looks like I am screwed lol.

Shaving your head would help 

Try an arai xd3 I fitted one to a guy who couldn't fit in anything else.

I have a Schuberth R1 3XL with internal sun visor and optional Pin Lock antifog. It's abslutely fog free down to freezing temps.

Before I got that one, I tried and liked a Shoei X1000 (?).

Last year, Arai launched a new Viper (I think) in 3XL. Same feeling as with my own.

IIRC Veimar have helmets up to 7XL.

My husband has the same issue.  He had an HJC in XXXL and then found an Arai Vector in XL that fit him!