case.qstatus will not work.

https://github.com/ESMCI/cime/blob/66dd00b0af206bc93a3ab83df739cddd33ad1e3a/CIME/XML/env_batch.py#L1392-L1409

Since the `root=` is not specified in the `self.get_optional_child` call and `"batch_query"` is not a child of `self ` in most cases but it's grandchild, it will return None. Since we have at list two children (one in config_batch.xml in ccs_config/machines and another one in the machine directory). The trival fix would be too loop through "batch_system" and take the last "batch_query" that is not `None`. Should I fire a PR?

Start at CIME/XML/env_batch.py lines 1392-1409 and inspect how self.get_optional_child searches the batch_system entries in config_batch.xml and the machine directory. Verify the case.qstatus path finds a non-None batch_query, then exercise the affected configuration to confirm it works.

Written by the indexing model from the issue text.