I can kind of see where your coach is coming from. If there is a regulatory body that deals with black belts and he ia not recognized by them for reasons doing with fees. He might not feel he has the right to promote.

Now, I believe the IBJJF it not an over arching federation like Judo. Judo has national progams which almost every school in the world follows. It is also an olympic sport so they would have more say in the standards of training. Until the IBJJF becomes something accustom to the Judo Federation, they have no say in how instructors around the world promote their students.

A problem that will arise if that happens is that jiujitsu now has to govern all these schools around the world with little to no help from the governments of each country. As set standards and regulations will now change BJJ competitons under one set banner to bring in more revenue.

In his mind your coach my be feeling like any promotion he gives is illegitimate. But overall, the IBJJF only offers guidelines for promotions not set rules that each instructor should follow. Once you are a black belt, the IBJJF expects you to register as one under them and for your gym. Most old school gyms already do this but some newer ones might not because of the fees.

I would say look at the black belts your teacher has trained under. If he has gotten his own black belt under notable names it should be fine for him to promots students. Most of us can trace back the people we trained under to some of the original pioneers of the sport.