I remember the first pantheon I did (was still a noob at the time) I was on the light side but had QoT selected. If i went into character selection I could only pick from light side, but I cancelled out and joined a game on light side as QoT. After I changed to a light side DG I wasn't able to switch back. I've seen the occasional wrong DG on a side in recent pantheons. I've tried to reproduce this bug out of curiosity, but haven't been able to. I know with my frist QoT problem, it was the DG that was already selected when i started the Pantheon, so maybe it's only possible the first time you start. Not sure, but one game I was darkness against a well coordinated sedna/oak/TB. Not sure if it was a premade, but they sure mopped the floor with us (never split up and had perfect focus fire coordination, and flag control). So maybe they were some leet doods who haxed the internets, or this is just some random bug we'll all have to put up with from time to time.
/shrug