As it's currently written the test uses a long-running $where query so that it has an operation to kill, but this can be more reliably achieved using the setYieldAllLocksHang failpoint. Doing so will remove the timing related assertions of the test such as this one and make the test more reliable.
To use the failpoint, we'll have to move the test out of core and into noPassthrough. While doing this, we should ensure we still get the coverage we want that we were getting via passthrough suites (e.g. killing an operation through a mongos).