The wifes 2006 Charger Daytona has a spare in the well in the trunk next to where the battery in mounted.

My 2007 300 SRT8 has a foam block with compartments in it in that well.
That's where they put the air pump assembly and fix a flat goo.

There's no reason you can't put a spare assembly in the well.
The main thing is making sure the spare fits over the larger Brembo brakes.
To use a factory spare a wheel spacer is required on the front hubs.

That's what I learn from searching using a space saver spare on the SRT cars.

Any later model with the larger brakes is where you have to make sure the spare clears the brakes, the front seems to be where the issue is.

The kit that the OP bought looks like it was designed to work with the larger brakes.