But the 'recipient' (of the NTO) didn't make reps.
While the authority is entitled to demand proof of authority in the form of an LoA from the person named on the NTO, there is no law that says they must. If you got an NTO and I sent in a representation saying you've authorised me to write in on your behalf, there is nothing to stop an authority saying "
OK Mr cp8759, we accept at face value that you are authorised", it might seem odd but I can't see that the council are breaking any law by doing that.
And if you look at the statute the legal test is not a two-part test, it's simply that the appeal has to be brought by the recipient of the NoR, whoever that may be. Otherwise if you get an NTO and you make representations against it but due to some council mix-up I get the notice of rejection which names me as the liable party and demanding that I pay within 28 days, I'd have no right of appeal.