That sucks. I guess they were aware that what was going on was dangerous from what I read. Also it seemed as if they were just lowering each other which backs up this more.
Just bring a second line and finish the climb and belay from the top is a way to avoid this. Then make a safe rap. Even if they did not know before hand they at least knew what they were doing was unsafe. I'm not raggin on anyone but the truth is the truth. There could have been other options.