Thank you for your question! I've copy/pasted some elements from the CRL's I found under the "additional info" section.
Quality Clause
"Some examples of instances where the quality clause may be invoked include, but are not limited to, materials used in construction, craftsmanship or construction methods used, questionable greeblies or props, attachment methods, and alternate color painting methods like glitter, colored vinyl stickers, wraps or hydro dipping in lieu of regular paint in large areas."
Face Character Items
"No unmodified parts or themes can be used from Star Wars canon/legends face characters. This includes, but is not limited to, lightsaber trophies, lightsabers/darksabers, paint schemes, symbols/sigils, and armor pieces/elements."
The only era that uses leather in large quantities is in the Crusader Era. There is no reference that I can see of a Modern or Post Imperial Mandalorian using leather wrapped Beskar. For those Eras, leather is mentioned in the CRL's for attachment methods, not as armor itself.
The best way I could answer your question is to say that if you want to do a Canon DeathWatch from the comics, read the CRL's for that character and work with your Ruusalor staff to accomplish that goal. As it stands right now, leather wrapped armor would not be approved for the above quoted CRL points.
Personally, I love the look of this helmet and you should be very proud that you crafted a beautiful piece. If I were you, I'd display that on your wall with pride. I wish you the best and happy building!