**Reproduce on main:**
- Run a DAG
- Rename the DAG
- Wait for dag file processor to remove the deleted DAG and add the new one. (Old Dag should not appear on the home page anymore)
- Go to the Browse DAGRUN page.
- Click on a DagRun of the deleted DAG, as if you want to see the 'details/grid' of that old dag run

More info and screenshots here:
https://github.com/notifications#discussioncomment-6898570

![image](https://github.com/apache/airflow/assets/14861206/7af81643-6278-4d90-a20f-6aa7b259ce59)



child_instances = [
                item
                for sublist in (child["instances"] for child in children if "instances" in child)
                for item in sublist
                if item["run_id"] == dag_run.run_id
                if item
            ]
            children_queued_dttms = (item["queued_dttm"] for item in child_instances)
            children_start_dates = (item["start_date"] for item in child_instances)
            children_end_dates = (item["end_date"] for item in child_instances)
            children_states = {item["state"] for item in child_instances}
            group_state = next((state for state in wwwutils.priority if state in children_states), None)
            group_queued_dttm = min(filter(None, children_queued_dttms), default=None)