The test clearJumbo is failing occasionally (BF-25252) because the function waitForBalancerToRun is not waiting a full round when there is a configsvr stepdown in-between the round.

Regarding the logs, when the configsvr recovers from the stepdown, the command balancerStatus returns an incremented numBalancerRounds. Logs with filters can be found here where you can see how the _configsvrBalancerStop command is called immediately after the "CSRS balancer is starting" because of a stepdown-stepup.

A quick suggestion would be to use the balancerCollectionStatus command instead of the balancerStatus cause it returns more detailed information.