That wouldn't be a bad idea. Another idea: maybe other players could work as NPC's, if they've already defeated the deck that the opponent wants to face? ex, I've defeated ffq. Thus, I could be given the code for the FFQ deck. I haven't beaten devourer yet, and thus a challenger shouldn't be able to challenge me as devourer, as I shouldn't know what that deck consists of.
I for one would love to help out with NPC battles. I've felt so bad for our NPC's this whole event, and wished I could help out. I've even considered dropping out of the event to take on an NPC role.