So is is safe to assume, if there are 2nd gen chips, that they share the same heat problems?
define second gen.
Pictures Ive seen of "first gen" suggest a plastic QFP package. Which is the cheapest, but a terrible choice for a chip that runs hot. In that sense the claim is credible.
If all these alleged 10000 chips are all already packaged, I dont think its solvable. If they still have unpackaged dies or uncut wafers, they could easily select a more appropriate package.