The key word is "Christian". I read it to mean that only JWs can accompany the minor. In my example, the guardians are not JWs.
The wording clearly says that "Christian parent(s) or legal guardian(s)" can accompany the minor. I can't see any non-JW parent or guardian getting anywhere near that meeting.
That was only a couple of suggested scenarios. There must be more examples of JWs who are minors who don't have JW parents or guardians.