So it's a bunch of self appointed individuals trying to insert themselves into positions of power over the game industry. If that's the case then I'll be appointing myself to the position of "Gaming Loot Box Czar" of the "Great Gaming and Gambling Commission of the Universe."
I do think that there needs to be some sort of industry group preferably of a technical nature, similar to the IEEE, rather than the ESRB, or the various state level gaming commissions. I don't think this is it, or how to go about it. These guys just seem like leeches based on the limited information.
If it must be a federal agency the ESRB is the natural choice. The ESRB could modify their ratings system to account for the predatory or benign nature of the loot box system. So something like Battlefront 2 would get a bump to a mature rating for their aggressive use of loot boxes to drive game play. Where as games without aggressive loot boxes would get flag for "gambling" similar to the "violence" or "tobacco use" flags they currently use.