I can speak on Cisco's system or software, because I have always been suspicious of Cisco due to how massive they are, no company gets like that without dirty dealing underneath.

I don't think Google forks Linux, they use parts of the kernel, and there's also OpenBSD security code in Android as well.

While Google is evil and I will rejoice at the death of Google, I hope they are successful in their new OS to fully replace Android. I think it's called Fusia. Software development is always better then GPL code is stripped out and replaced.