Discolor Bug/Glitch - Affected Helmet "Hood of the Silent Assassin" - Night Elf only Issue - No Fix since Shadowlands

Hi. After I switched from the Alliance Race “Human” to my Current Race “Night elf” my Helmet has been appearing with a strong “Dark/Black” discoloring. The item itself is called “Hood of the Silent Assassin” which is the Helmet piece from Armor Set “Silent Assassin Armor” from Mist of Pandaria.
This Set has a high value for myself and others who might experience the same issue consider its extremely rare and wanted Armor set from the old days.
Every other Body Piece in this Armor Set appears correct on my Night Elf, it is only the Helmet which is discolored. I can note I have made several other Characters with different Races, and it is ONLY Night Elf which has this discoloring which is quite weird.
Troubleshooting on the Internet on this is impossible considering the Item rarity and most similar issues are by White color not Black so I have a feeling this requires some work inside Technical Support? I have also tested both the Male and Female version of Night Elf with no luck, it seems to follow the Race itself.
I have also tested creating a new Night Elf Character wearing the same Transmog with same result as stated above. I have experienced this for a couple of years now, any ideas how this can be fixed? I cannot switch Race consider it is my favorite since Classic days and the best for my Class. All love and thanks for your time reading, have a great Xmas.