Was the rest of the Austrian force in a bleak situation at that time? Would it be difficult to bring reinforcements in?
Seems like if they could have held it longer it would have been a fantastic bargaining chip for a beneficial peace treaty
As far as I Know the whole thing was only designed for the purpose of obtaining money from the city (in which they suceeded). It was only a small part of the Austrian army, and when the king of Prussia send the Prince of Anhalt Dessau with an army to Berlin the Austrians left immediately with the ransom.