Just scroll back in this forum a couple of months or so, there are several multiple page threads that are basically FAQs on the Cuda Maxx. One of them, I remember was started by Maurice.
Boron Carbide coating is done by an outfit called Bodycote (maybe BodyCote). Do a search for them and for Darrell G Lewis. He works for them and posts here and some old threads explain all about it. You may have to try some variations on the spelling of those names. or just search for boron carbide, and look for threads started by Darrell G Lewis to get the correct spelling.
The anodizing doesn't go black on titanium, it would have to be blasted off and BC coated to get black handles. The anodized handles on the Cuda knives are some combination of blue, purple, gray, and several other weird colors I have no name for.
As for who does these modifications, except for the BC coating, these guys are working on their own knives. I took the knife down and used a Dremel in a router table attachment to stone all the tool marks out of the flippers. Then hand sanded the blade flats.
BTW, the BC coating is not real jet black like a Benchmade coated blade, more like a very, very dark gray. Looks better than black in my opinion.
Oh wait, I may have lied to you about titanium not being anodized black. It can get pretty dark, if not black. It won't be on the Cuda
knives, though. I just got a Ralph 4" Maxx with a BC blade and the handles are very dark grey down the middle with hints of purple around the edges. Pretty understated compared to some of Darrell's knives.