There are shares to short. It is probably being shorted down right now. There were 200k available on Interactive Brokers this morning. I saw 100k available a few moments ago. The big shorts aren't dumb. They will dribble out covering if they can so impatient or nervous longs sell their shares. Technically the daily chart looks like #$%$, except for the huge volume reversal which may indicate a bottom. We just have to wait and see if that gets confirmed.
YOU do the math! If there are zero shares left to be shorted, wouldn't that indicate that shorts are literally exhausted, i.e. cannot go any further? From any point of view, not much reason to sell at this level.