What “Interface Control” would that be?
You might be able to use the Press a Button action to activate the M.V. tab, but Keyboard Maestro can't always see this sort of control.
The pop-up menus cannot be accessed directly.
You'd have to turn ON “Change the way Tab moves focus” in the system keyboard preferences – tab to your desired location – use spacebar or return to open the menu – type the number to select the desired number – and then return to confirm.
I find this awkward and sometimes unreliable, but sometimes it works perfectly well.
Found-Image might be the way to go as @Sleepy suggests.
@hello's suggestion of using System Events is likely to be the most flexible and reliable method if the most difficult.