LEDs flicker but Halogen works fine
Option 2 is the cleanest solution to your problem, since &quot;non-dimmable&quot; LEDs hate dimmers and behave strangely with them, as many dimmers do not bypass themselves even at &quot;full&quot; brightness.
I have an LED compatible dimmer and dimmable LEDs where I replaced the dimmer with  a switch simply because the dimmer was causing an irritating audible noise in some of the LEDs that a switch did not. It also kept them from getting quite as bright as they could, and had an annoying 1/2 second delay when switched on.
I doubt you'll find a Halogen that will match the color of your LEDs, but if you can stand having one bulb look different it saves the cost of the electrician, especially if this is a rental.