This has already been answered in the Irene forum. I understand that your team has decided on strict guidelines for the use of uniforms to reflect your unit. The reality of these ops and many others is that you will need to wear different uniforms to conform to team play. They are not individual team based Ops, but military simulations that will more often that not require you to conform to a uniform utilized by current or prior military units. As there are no large scale military units that use Black BDUs then I would not be overly optimistic about finding ops which allow them as a standard uniform. Sure there will be some that will allow for Freedom Fighter or PMC type units but by and large most use DCU or Tan vs BDU or Woodland camo.
An idea to pose to your team would be to keep the Black BDU uniforms for home and local play but create unit patches to use on DCU or Woodland BDU uniforms to distinguish yourselves in larger national Ops.
Best of luck to you and take some time to look around.
Op NS 3,4
Op NW 6
Op BD 4
Op Irene 8
Op LC XI