Yea that sounds about right, really hiding root is straight up magic as is (even though it’s a cat and mouse game lol) and achieving that is 98% of the hard work of hiding the fact an app has been sideloaded. Short of a complete overhaul from Google where they actually try that is.
Which, if I’m being honest, doesn’t seem like they are. It seems like a rather simple system all things considered. There’s no Playstore specific keys or signatures or file checks or hashs as far as I can tell. Its just a flag and checking if Playstore exists on the device at all