The easiest way to solve this, is to change the data control scope to isolated for the popup task flow group.
This way the task flow gets its own am instance and will only rollback its own data.
Thanks Steven. On testing, this was BLAZING fast. However, it means passing keys between the parent and child taskflows. Fortunately I already pass around the keys and an iterator as it will require finding the information interested in the new data control scope.
Have a great day!