I used the "Hub Variable" rename feature to rename a variable tonight.
It properly renamed the rule references, but it did NOT rename the references in the dashboard (this was a "full function" dashboard, not an EZ one).
The variable I renamed was one of the variables selected (checked) in the "Choose Variables" list. It was placed in a tile on the dashboard as a variable.
After renaming, the new name was not checked in the "Choose Variables" list for the dashboard.
And, in the "Layout JSON", the "globalVar" line was not changed to reference the new name either.
Manually selecting the renamed variable in the "Choose variables" list and manually editing the "Layout JSON" to use the new name in the "globalVar" line for the affected tile was the workaround. Making those changes and clicking the "green circle checkbox" on the dashboard to refresh it seemed to do the trick.
This was repeatable, as the same scenario occurred when I renamed a second variable.
Thanks.