Great insights again, thank you! Holding the call was a great idea but unfortunately it doesn't seem to fix anything on our side. At this point I guess we're just going to cut our losses and live with what we have until we can implement the whole thing natively.

Hi Kevin, Thank you very much for taking the time to write such a clear and detailed answer! It does indeed match my experience with it and it's quite unfortunately but hopefully this thread will help future people struggling with the same thing. I believe there's also a 3rd option in which we keep the native CallKit ringing and redirect to the main app but end the call before presenting the web app. It worked pretty well for us so far but I'm going to have to test it further.