This is an assumption on the parts of ChipWorks. It may well be correct, or not. One problem with this premise - it is based on another assumption: that Apple is producing millions of smaller versions of A5 (APL2498) and are picking off some of the defective ones to use in AppleTV. So Apple is already manufacturing this 32 nm A5 in sufficient volume that one specific defective species is sufficiently large in quantity as to supply another product line? Pretty big assumption.
What you are saying is also right and I think no one but Apple and the vendor that fabricated them know about it.
However, if I am not mistaken, TSMC is the supplier of these devices. Based on the experience that I have had with TSMC their yield is usually low! and we were not even working at 32nm! Their yield should be much lower at 32nm but if they can recycle it like the way they have done it, then it would be worthwhile!