"Also, his Egyptian name was Sutekh. He was never called Sutesh, but he was called Setesh. And if anyone wants to argue, I am a Set EXPERT"
You've obviously spent many years researching your novel, travelling to Egypt, excavating your own private burial mausoleum complex. . . . but I'll argue anyway! It's fun!
I find it hard to believe that you know for a fact that Seth was never referred to as 'Sutesh.' In order to prove that he was never called this you would have to manually research every single reference to the God in existence. It goes without saying that this is impossible, as I can state with conviction that not all the texts in which Seth is mentioned have been discovered.
His Egyptian name was not merely 'Sutekh' or 'Setesh' anyway. To name but a few alternatives, we could have 'Iyat,' (lit. the painful one) 'Setkheru,' 'Iyasha,' (lit. the roarer) 'Eb' (the hissing serpent form of Seth) 'Setjemseret,' 'Khabalet' or even 'Ur-hekau,' (lit. the one who is great of magic).