Found a fix!
There is a UnitPanel.xml file that didn't get properly removed in the latest update, so it seemed to be causing a conflict with the new file they added for R&F. If you remove that file, the new one will take precedence and the UI will work properly.
To find the file, go to the local files (in Steam, right click the game ---> Properties ---> Local Files ---> Browse Local Files...), then navigate to the UI assets folder (...\Sid Meier's Civilization VI\Base\Assets\UI). The UnitPanel.xml file should be in that folder.