The afterEach hook's ShardingTest.stop({skipValidation: true}) call still unconditionally runs checkMetadataConsistency(), which is not gated by skipValidation. This test deliberately stops/restarts the replica set and mongos mid-test, so by the time checkMetadataConsistency opens its own fresh connection to mongos, the process can already have exited, causing a spurious connection-refused failure in cleanup rather than a real test failure.