I kinda like this idea.... You can manually change the filamemt colour and type in the app or the slicer. So the function to use the second spool after the first spool runs out will still work. It really is only the auto detection that will not work.

The filament/color detection is only when using BL filament. That sensor only reads the NFC chip in the spool. You can set the color and type of filament manually. The system will change filament if you tell it do so manually.

I'd bet spool holder act to tell it if there a spool on it, so you'd have to bypass that. so it thinks its always loaded. it likely doesnt try detect on an empty spool, so you have to lie to it. But then you'd lose the function that tells you how much is left on the spool. none of that matters if you other brands of filament though.