Kick reason is sometimes absent for federated calls

[AndrewFerr]

Steps to reproduce

1. Set up an Element Web to allow guest links
2. Create a public room & start a video call in it
3. Copy the guest join URL and have a guest join it (unsure if the guest needs to be on a different homeserver)
4. Use that link to join the call
5. Have the creator of the room kick the joined user with a reason

Outcome

What did you expect?

The Element Call SPA for the guest user should show the kick reason, like so:

This does happen when the room the guest is kicked from is a knock-access room or a public video room.

What happened instead?

No kick reason is shown:

Operating system

Fedora

Browser information

Firefox version 125

URL for webapp

Development version (5284479e)

Will you send logs?

No

[AndrewFerr]

This doesn't always happen, as I was able to see a kick reason for a public room call just now.

Perhaps what triggers this is unrelated to the room visibility.