In HELP-83278, the killOpThread got stuck while trying to check out sessions in order to abort unprepared transactions. There was a timeout added to some of the abort transactions code as part of SERVER-77172, but the timeout value was not passed through all code paths. We should consider adding the timeout to the step down code path so that this thread will eventually time out and not block step down from completing, or generally consider an improvement to the session checkout code to prevent the thread from getting stuck here.

In addition, I think we should also add more observability to this area of the code because it was unclear where in the checkout code that it got stuck (though the HELP ticket was on v6.0, so this may have already been improved.)