Do you have Settings > Apps > App Store > (Automatic Downloads) App Downloads turned on?
I noticed apps appearing on my Home Screen I’d never heard of before. Turns out with that setting and Family Purchase sharing turned on, every time my wife installed a new app, it installed on my phone too.
That may not be your exact scenario, but I wonder if turning off that Automatic App Downloads setting (if enabled) changes anything. Could give you a clue, if so.
App Downloads and App Updates are both turned off. I don't have anyone else's devices on my account, just me. Thank you for the suggestions though!