There is no such thing per se as "TY dye Verbatim discs", :disagree: and Verbatim TY actually IS "true" TY.
Taiyo Yuden manufactures the discs, Verbatim sells them under the Verbatim brand. As simple as that. I think that even the branding (Verbatim logo etc...) is made at Taiyo Yuden factories.
Looks like you've been mislead by a common misconception about media, sadly widely spread on the net, i.e. that the mediacode is the dye used, and that for example Verbatim TYG02 are discs manufactured by Verbatim with a TYG02 "dye". That is entirely incorrect.
Actually, the mediacode is the model of the disc, and indicates the actual manufacturer of the disc, whatever the brand it's sold under (unless the mediacode is faked, but this is another story). There are very few exceptions to this rule.
Now, this doesn't mean that there's no variation in quality from brand to brand with the same mediacode. :iagree: (another widely spread misconception).