Datasource Templating with Inline Substitution

I have several sets of cluster-specific datasources where the cluster name is in the middle of the datasource name, and I need to repeat panels vertically by cluster. Is it possible to use the inline variable substitution (the double brackets) in a datasource name for Grafana 5?

i.e “testEnv.[[cluster]]_dataType” where the panel is configured to repeat vertically for the values of “cluster”

When I type the string into the datasource box, it just jumps back to the previously configured datasource name. I also tried manually inserting that into the dashboard JSON and then importing the dashboard, but it does not load the panels properly.