The noble families weren't asking for Silver Mirror's favor. They were willing to pay him a large amount of money for their safe passage. This still put Silver Mirror at a crossroads.
Silver Mirror had to decide if he would take the money and help the nobles while risking offending Bushwick or refuse to help the nobles while waiting for Bushwick to come and deal with him after the rank 4 noble is done dealing with the noble families.
The boss of the underground black market was clear that no matter what choice he made, Bushwick wouldn't let him go. It was just a matter of time before Bushwick came after him. So he was inclined to help the nobles and earn money.
When Bushwick heard that Silver Mirror was helping people to escape from his grasp, he became incensed. He was so angry that he destroyed many vases and plates.
He was angry, but he didn't plan to attack Silver Mirror and the nobles because he wasn't sure that he could defeat all of them together.
