Yeah, and they might be using one method to connect to your relay for the purpose of displaying that it is "online" and a completely different method for actually sending it notes, such as via a proxy, etc as nostr:npub1a6we08n7zsv2na689whc9hykpq4q6sj3kaauk9c2dm8vj0adlajq7w0tyc mentioned above. So even if your client is able to connect to your Tailnet, the notes still won't publish.

I am guessing the same issue could happen with a Tor-only relay for the same reasons. Even if your client itself is connected through Orbot, if it is using a proxy to write notes to your specified relays, it will fail unless that Proxy is also connected to Tor.