All the stats are wrong. Personnaly I have win match reporte as lost, match that I never played, duplicate matchs reported as custom Lost, win match never reported in the stats... I think you can ignore the pantheon/ranking until it will be fixed. I really hope then all stats will be reseted. No point to keep track of falses stats.
EDIT: Just gave a look at the stats of the player, it's really suspicious. Look like some exploit of the stats bugs (or the guy is really lucky and get a won game duplicated 10-20x).
Please, fix the stats an reset them!