due to the high demands of trying to run 4k maxed visuals, can or is mGPU support available in a patch or plan?

mGPU... do you mean mobile GPU ? If yes, dedicated gpu or integrated..

mGPU means multiple GPU.

Recently i helped a facebook friend, he was running 2xAsus STRIX-R9 390X @ crossfire.
He was not able to run the game.
He is now using 1x Asus STRIX-R9 390X with no problems.

Not sure it is a problem with both cards using crossfire or this game has problems with this.

Supposedly with the older Nvida drivers that worked with checkerboard rendering you can force enable it but I can't get the profile inspector to stick on cyberpunk yet.

Vulkan support would have been nice but there's no info on Mgpu or vulkan for steam or GoG right now.

Crossing my fingers for the next patch to have something to help us multi card users.