New iOS client cross signed is not trusted by other clients, rename of client not recognized

I setup a new iOS client with my matrix.org account.
Cross-signing is enabled and key-Backup is enabled.

My new client was just recognnized as "Tablet", so i decided to rename it to a "spoken name"
or detailed here

All devices are shown with a green shield (all verified)

I thought that since cross signing is enabled and E2EE is enabled between clients, a new device that has been verified by it's owner should be trustworthy for all other trusted clients either.
But this is not the fact.

As you can see here:
and here

From the point of view of a chat partner the new device is
a) not shown as it's device name after renaming
b) not trusted, but i can send and receive encrypted messages from this untrusted client.

I am not sure if this is really an iOS problem or a generally cross-signing / verification problem, so someone should investigate that who is able to understand what happened between those clients.

As seen in the screenshot above there is a verification method by text or emoji offered. I followed this on a android device.
On that android device same situation looks like this:


The device that is shown as "Tablet" is my new device that shoud be shown as "iPad Pro LFS"
But the device is trusted here. But my account is not, it now shows a red shield since login to matrix.org from this new device.

How can i again trust a client "chrissi55" that is shown with red shield besides his nickname but from whom all devices already have been verified and no longer "verify-button" is offered??