Custom Immersive Background without removing actual background of participant

I would like to create a custom immersive background that functions exactly the way Art Gallery 5 functions.  When the participants are within the frames, Zoom keeps their background untouched, not cropping around their heads. 

I am able to create a custom immersive background without any problem...however it's removing their backgrounds behind them.  This is the same behavior as all of the other pre-installed immersive backgrounds.  They remove the background to place the participant in the scene more realistically.  That's not what I want though.  

Anyone have any thoughts? 🙂