I'm not too sure about that. Your construct that in any creative field you cannot exert influence-" but he didn't actually make any music " does not stand up to scrutiny.
Here's a few influencers for starters on black music who didn't make any music:
Jim Stewart, Estelle Axton, Alan Freed.
You could go through all the arts, painting, literature, music and find many influential figures who either created a scene or propelled it, into a sub culture or mainstream, without making the product.
Anderson unearthed and rescued many black artsits from obscurity. His tenacity also tailored the music that found it's way on to the dancefloor and shaped listening tastes throughout the land. So in my mind he was a major influence in black music.