Oh man I wish I knew about this bug before I upgraded to Android 11.
I had version 884 and it would not find any downloaded files. So I uninstalled it. Now the Play Store will not re-install, says "CAN'T INSTALL Poweramp MUSIC PLAYER (TRIAL)"
I tried rolling back the play store app and re-installing it, same problem. So now any podcasts I downloaded through Chrome are sitting in memory and cannot be found by Poweramp.
VLC player can't find them either, so you're not alone 😢