For one char and all enemies time stands still in combat. The other chars have all the time in the world to sneak past vision cones and do another alpha strike.
I think this could be avoided if they had made pause work on the entire world. You can move everyone into position for the ambush attack then initiative should immediately start for everyone. Even if you leave party members back until later in the combat then they should still get only one attack before being added to initiative.
