Those 'dots' seem to have shadow which would indicate they are on the outer surface of the disc and not the inner metal layer. But, the angle of your flash seems to negate this.
In any case, I would take the discs back to the store and ask for a replacement. If like most stores in the US, you won't likely get your money back or a different product. But if you simply want to replace a defective product you should be fine. If the store will not help then you will have to try the publisher I guess.
If those dots are not on the surface and fixable, I would certainly not trust them. I've not seen anything like that before.
Just thought of something. If those dots are small wholes in the surface of the plastic, that would possibly explain the shadows in relation to your camera flash. Maybe you can examine them VERY closely.