Shortcuts, Sleep Timer with Music, and Standby

So, I've set up a simple shortcut to set the volume on my phone, play some sleep-helpful music, and set a timer to stop the music after a period of time. No problem there. However, I use the Standby feature at night, with it set to automatically have the screen go off (and on) dependent on whether there's motion. When I start the shortcut and the music starts, I have to swipe up to clear the music screen, after which it goes to Standby mode. However...the auto screen feature no longer works, presumably because the music app is open in the background. As far as I've researched, there's no way to use Shortcut to close an app, so what happens is that the display for Standby then stays on all night. Not the end of the world, but not what I'd like.

Is there any solution to this?