1) Trust ratings are almost never moderated.
2) He's not in default trust, thus his ratings are not visible by default nor effect you by default.

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Conclusion: If he/she/it/they do not want to remove their rating, there's nothing that you can really do about it. I have a ton of false feedback on me from butthurt people that I've busted (not saying that Timelord's feedback is or isn't false though).