It is the Gigabyte X399 Designare EX, missing the middle hole in the top row, there is a heatsink where it should be.
I used a dremel to remove the standoff in the case to make sure it did not make contact with the PCB.
I would have loved seeing the MB standoffs being screwed in with a supplied tool or head for screwdriver, so that I did not have to dremel it : P
Other than that I'm happy as can be!
Screwed standoffs would be nice as it also adds compatibility to mATX boards to the CerberusX!
No idea how it'd affect cost and manufacturing difficulty, though.