Me and my friend just did a duo run of Aberus from Dragonfight on mythic dificulity, whenever i went after the last boss to catalyst my items that are useable by me and not tier, i catalys my back item that drops from the first boss, and for some reason it gave me an item called [Lingering Phantom’s Drape] (Death knight set) instead of the Paladin item called [Heartfire Sentinel’s Pelerine], my friend who got a different cape from Zskarn also confirmed that upon catalyzing his back he received the same cape (aka [Lingering Phantom’s Drape]) (he was playing Evoker).
Further more we did a Vault of the incrantes run, and he had the same issue where the cape defaulted to the Death knight cape after catalyst and not the Evoker one