> Intel didn't have access to samples of enough AMD stuff, or the wrong department had it, or they couldn't get approval to take the time it would require
You'd be surprised how bad communication can be in a big company the size of intel. I'm sure they have plenty of samples of AMD stuff, but I could believe they're being used mostly by some cpu-testing division, rather than the open-source one.
I wouldn't be surprised that communications were bad within Intel. I also wouldn't be surprised if there was zero political will to make sure their contribution worked properly on AMD processors. Combine the two and you get whatever plausible deniability you want to use to deflect the argument, I suppose.