if they are wrong, "I am skipping the stream to have a chat with x about y" can be interpreted any differently than, "I will have a chat with x. The chat will be about y"? But apparently it's Ausie... So I don't know.

they're largely the same. Y could also be a person or a non-person topic or possibly a time.

Yeah, it feels that the "about y" is subordinate to "chat with" which apparently didn't make sense to this person. "Perhaps there is a cultural difference" where I'm Canadian, and he's Australian.