Yes, the blower pipe that directs steam up the stack to create a draft when the engine is standing, came lose and did not send to the steam up the stack. As long as a locomotive is working, the blower is not needed and the exhaust steam up the stack creates the draft. It when you are stopped you need the blower.
Wood burners have an addiitonal issue in that there is no bed of glowing coal and carbon to support combustion. Unlike a coal burner, when the throttle is closed, the fire dies down very quickly. To keep the fire alive for a full-throttle start, you need lots of blower running, while stopped. This is where the Eureka met its match. The fire died down, dispite the blower valve wide open (and not sending steam up the stack). The injector was running to get the water level back up, nocking the steam down faster. Soon, the steam pressure was so low, the air pump could not keep the brakes pumped up.
Eventually, the Eureka's crew came up with the idea that something was wrong in the smokebox. The opened they smokebox door and found the displaced blower pipe, and managed to correct the problem. But by then the decision to annull the tran had already been made.