AbdulAlhazred
Legend
Opposite Sides: To flank an enemy, you and an ally must be adjacent to the enemy and on opposite sides or corners of the enemy’s space.
The rules text actually does specify precisely that, in exactly those words.
Yes, but the part of the rule I quoted above is a whole other clause and only talks about "you" being able to make an OA. Like I said, I think RAI is you both need to meet all the requirements, but there is enough of a hole there for rules lawyers to drive through...