Deriel (Inquisitor) was blocking Magnus, and then he was killed, which is why he doesn't have a Night Duel today.
Abbat was blocked today, maybe by a Mage or an Inquisitor, and Deriel was Abbat; it's a random block.
Red was a White Mage, and he was killed by a Warlock, hence all the references to the song.
there are many versions, and I don't know which one is correct.
never mind, the main thing is to suggest, and then think about it and look for the answer.