it is possible for everyone to go online with the same save but the unique header information would have to be shared also, at least at this time
Right, that's what I was afraid of.
I created a save with a player named "EventGrabber" for use getting legit wonder cards, I redeemed both my Scizor and Garchomp codes (separate saves, each one has one or the other)
But then I realized it was locked to my cart's header. Whoops
On the bright side, from what everyone's posted, it's not likely there's any real "unique" data in there after all since you can just fudge the numbers and it'll still work. So I should hopefully be safe from being banned when playing my legit game.
Was just hoping there was a way to set it up so it could be shared without needing the header