why dont you post some photos of setup and what your average meal looks like. average...dont make him up something special for picture day. lol.
Many BT's will lose appetite during "blue" phase of shedding.
Purchase a mini-food chopper... so you can mix small pieces of veggies in with the meatier "chunks". Get him used to the taste.
And I still say, let him go without food at all for 3 days then try the nutritous diet.(only if he hasn't had weight loss). then mush all the foods together.
Boris with his first meal...getting him used to the taste of Collards.

only 4 months old in this one...


...thinking about dinner...

...done thinking...

or if you like high-end specimens, check out Andrew Seike's Sunset Northerns...

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1 Eastern Blue Tongue Skink
2 Tarahumara Mountain Kingsnakes - Knoblochi
1 Thayer's Kingsnake - Thayeri
2 Golden Greek Tortoises
1 Pyxie Frog - 14 years old