Precisely. So their pulled under with the sinking of the plane of the assistant holds on to her causing her death. If not by drowning what? Strangulation?
If you don’t grab the flailer by the chin (firmly, you go under them and turn them around by the legs first), they will drag you under trying to climb on you. The hope is once they are firmly in your grasp, floating on their back while you kick/stroke towing them in, they will calm down.