Using Callkit as an alert

My client is developing security lock and would like to display a full screen alert when something happens to the lock. Only way I found possible to display such alert is using CallKit and display UI of incoming call.

The logic would be - something happens to the lock, it sends info to BE -> BE sends VoIP push notification to app -> app displays incoming call UI (accepting or denying the call does nothing except hiding it)

Will Apple even allow us to do this? I am familiar with critical notifications, but that's not what client wants.

Using Callkit as an alert
 
 
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