PPS. I did quite enjoy the passing reference to "Mac and Tosh", the Looney Tunes gophers; I remember them fondly. I have to admit that I also enjoyed the use of Force mind control on the librarian and on Filch; I wonder what Albus will make of Filch's behavior?
One other thought as to Harry's proxies, perhaps a suitably high-ranked goblin? I'd think that having such a personage present would be considered a show of honor to the Wizengamot by the goblin horde (though the more extreme purebloods might not take it that way).
Author's response
It took me SO LONG to find out who those two were!
Pince: What he doesn't know, can't hurt Harry. Unless he has a reason to look at those books and probes her mind, he'll have nothing to suspect. Since he feels he is omniscient, that's not very likely. By the first of September, the point will be moot anyway.
Don't worry about Filch. It'll wear off.
In time.
I seriously considered having Graswold as a proxy, but the Wizengamot, is a 'good ole boy's club'. They would never allow a goblin, for any reason, to sit on the council. If it did somehow happen, they'd take steps to neutralize his vote, and Harry is going to need that vote.
Alorkin