Earlier quoted context omitted.
But they have to fake the voice, if I call the other person and say "my emoji sequence is this, this and that" for the other person to verify and vice-versa.
Person A calls you. I intercept the call, so person A is calling me , and then I call you (spoofing so I look like Person A). When you pick up, I pick up, then I transmit what you're saying to Person A (and vice versa). How do you know I'm intercepting the transmission? Does the emoji sequence verify the call , perhaps?
I'm not a cryptographer, but that's what I glean from their explanation: https://core.telegram.org/api/end-to-end/video-calls#key-ver...