SOunds like you had the cornish cross and they should not be tough even at 10 weeks. LInda brings up another good point-- how the carcass is handled AFTER processing. I can put mine in the refrig for a couple days , then roast up. I have hear of other, but not doneit myself, to pull out of freezer and let sit in fig for a few days to get the rigor out.
Try , try again.
Try , try again.