Wow, Cerburus - there's an app I haven't heard about in a long while. I do remember it being really handy back in the day... I guess that must have been around Android 4ish that I used it last?
As mentioned above, there are a number of security concerns regarding the Cerberus Anti-Theft app, and it having been removed from the Play Store for violating policies isn't a good look either. There are other anti-theft / "find device" apps still available through the Play Store so I don't think it's a case of Google simply trying to shut down competition for their Find My Device service (which doesn't make them any money anyway).
Personally, I would ditch Cerberus and go for another solution instead. Many could likely be augmented a bit with Tasker or a similar automation app to provide more capabilities while still preserving the Play Protect protection.
If you're insisting upon using a potentially insecure app, though, try going to Settings > Security & privacy > App security, tap the gear icon at the top of the screen, and disable Scan apps with Play Protect and Improve harmful app detection.