[emptysongglass]

The security analyses I am aware of target MTProto 1 which is not MTProto 2 used for quite a number of years now. MTProto 2 uses standard security primitives.

You cannot say "it is not correct" without proof. We know all messages not just E2EE are wrapped in encryption on their way out a Telegram client and we know they are decrypted on their way in because client source code is available.

Why don't you have a look for yourself then let us know if you've confirmed your suppositions?