As it existed, it didn't have any of the equipment needed to lower it. It was raised to it's position with temporary equipment, then the cables that held it up

As it existed, it didn't have any of the equipment needed to lower it. It was raised to it's position with temporary equipment, then the cables that held it up were fixed in place, and then the temporary equipment was removed. So to lower it, they'd have had to do a lot work adding stuff near the cables. Which they already knew to be a lot weaker than they were supposed to be, and of which two had already failed. That would have been the really negligent thing to do, instead of just removing all people from near the dish which was done.