The brake inspection week is August 23 through 29, and this round is the drum and the rotor.
A crack you can see, or a rotor worn down until the vents show, will park the truck. So will a drum with a piece missing. Broken metal does not stay on the wheel. It comes off in traffic.
Look this week
You have about twelve days. That is enough time to fix a drum you can already see. It is not enough time to order one and hope it arrives. Check the visible part of the drum and the rotor on the pretrip, and write up what you find.
A truck put out of service on August 23 is a truck that should have been in the shop on August 11.