This can happen with every manufacturer.
Two isolated incidents are not necessarily indicators of a tendency, but you should contact the shop and Taiyo Yuden to let them know. Even if they ignore you, they will become aware of a QC problem after enough reports.
I always preferred YUDEN000 T02, TYG03 and YUDEN000 T03 over TYG02, and now I know why. The other discs are tougher than TYG02.
TYG02 is often reported to have bonding problems. I'm surprised that YUDEN000 T02 isn't used more instead of TYG02. Yes, it may be slightly more expensive, but isn't it worth it?
If you already buy Taiyo Yuden instead of cheap manufacturers, you should go the whole hog and get the best from them, leaving their worse stuff aside