The _shardsvrShardCollection command doesn't wait for the config.cache.chunks entries to have been written on itself (i.e. the primary shard for the database).

Note that while _flushRoutingTableCacheUpdates would wait for the config.cache.chunks entries to have been written, the _flushRoutingTableCacheUpdates command is only run by the primary shard for the database on all of the other shards owning chunks for the now-sharded collection.

The resharding_collection_cloner*.js tests should be updated to explicitly run the {_flushRoutingTableCacheUpdates: temporaryReshardingCollection.getFullName()} command on the shards.