The only requirements are written in the Advancement Policies book. Not a relative and not a SM or ASM (as well venturing equivalent.) Other than that it is up to the DAC. Personally I think the people sitting on the board should be the Norman Rockwell eagle caliber people. (Not necessarily eagle, but the same caliber). Either the DAC is unaware of this persons character, has a different opinion, or does not care.
I would quietly bring it up with either the district committee chair or the district commissioner.
Oh, and congratulations to your son. He is wise to realize that EBOR members do not reflect on him or his achievement.
Venturing Crew Adviser, Assistant Scout Master, Renegade Merit Badge Counselor
Owl-2 WB 92-49
Foothills District Atlanta Area Council
I never teach my pupils. I only attempt to provide the conditions in which they can learn.--Albert Einstein