Sorry for the late response, haven't been checking Hive lately. Ok, so...
I have the link to the forum it came from:
Index of /43773/
Given that the resources here fit the ones in QP's original map (to a tee), I'm inclined to think this was an old forum he used.
As you can see, the Swan Knight parts are here.
Since I've only found this Swan Knight model in the LOTR Risk Stronghold map and on that forum, I'm confident QP is, in fact, its creator.
If that sounds a bit conjectural, I'm afraid that's because it is.
An attribution and general ownership is probably the best I can manage, unless you want me to message QP again and specifically ask after the model.
The thing is, I'm not sure I'll get a more specific response from him; QP is Russian and our communication probably won't be as exact as you'd hope.
Still, that seems to be what you're after, so I'll dig up his current e-mail account and see if I can get something more definite.
It is possible QP isn't the creator, but the impression I got from him is that he is.
Edit 1: I recall there were some credits in QP's map (so if QP's not the model-maker, we might have another avenue).
Edit 2: Ok, we're in luck - it seems only the credits "title" is in Russian. Here it is:
_________ _______ ________.
NEOF, UserX, Desperadoss. Belfegor, PapaTrust.Melganis.Erkin....
In the past, I did look into these people, but I couldn't find anything to link them to the Swan Knight, which led me to believe it was QP's original creation.
I'm going to message QP in a moment; hopefully we'll get a response sometime in the next week or so.