As a person who regularly signs players to the D-Leagues, I like the idea in the OP. I agree, however, that it is probably NGTH.
If it can't happen, why not eliminate D-League team forums entirely and replace them with a site wide D-League forum accessible to only those with a player in the D-Leagues? Team forums at that level aren't helpful anyway since Rookie/Soph D-League Teams only have 5-10 human players and no one uses the forums. Any information in the forums is also often outdated and can only lead to confusion.
With a site-wide D-League forum (which I would envision only for the Rookie/Soph level), there will be a larger base of people to try and get some conversation going. Anyone who wants to mentor new users could also simply create a D-League player to gain access to the forum.