My disclaimer here is that I really don't know since I have never used the
DAS system myself. However, from the new explanations of the magic band-linked version of the DAS, it sounds like once someone is linked to your MB, they stay linked until the DAS expires. So it would be very possible for someone who goes often with different guests (AP holder) to have a large pool of guests linked to their DAS, even if they only take a few onto each attraction with them.
If that's the case, I think it's possible that Guest Relations would allow all 17 to be linked as part of the DAS-holder's group, but keep the more normal limit of how many can be scanned for each attraction (DAS holder + 5 guests, I think). I think the OP was okay with that -- that only 6 people could use the DAS for each attraction. The OP just wants the "pool" of people to choose from to include all 17 members.
I think the 'exceptions' are for when you have a group that wants more than 6 people to be able to ride via DAS at the same time (a family of 7, for example). I think it would be unlikely that they'd let all 17 people ride via DAS as a group. However, I don't think that's what the OP is requesting.