No, that is not why NE isn't on the list.
NE is not on our list, and will not be on our list of recommended vendors because it is an unapproved recast (from the perspective of the makers of the original armour). IE, that is the bad kind of recast.
It is however (like many other recasts, good or bad) 501st approved as long as it is assembled properly and fits its wearer. But we at FISD cannot recommend it because of its origins.