I supopse they may have some basis for wanting to say a 'request' for a cancellation was initiated. There may be circumstances where, for example, a passenger has bought a return ticket but has only travelled one way. Or has bought a one way ticket but decided to break their journey part way through. In both these cases there may be additional fees or charges associated with that 'early' cancellation. (Airlines oftne threaten this, but rarely seem to pursue collection.)
But I'm not sure that even that argument holds. If the passenger wishes to cancel, they should be free to do so, even if it would result in additional fees.
I think you have summed it up. But for QF's inaction, you would have suffered no loss.
As I mentioned before, I think the issue here is that this case just hasn't reached the right department. This is a legal issue, not a general ticketing or fares issue than can be handeled by reservations or by frequent flyer. Once it gets to their legal department you should get a more definitive response.