Google could release evidence showing that certain MPEG-LA patents are almost certain to be invalidated if tested in court. But MPEG-LA would never acknowledge this; they'd still mumble things in public about forming a patent pool and so on. Not everyone has a sharp enough in-house legal team to weigh up the true threat; most would look at the situation, see that there is some legal uncertainty, and decide to play it safe. Remember what the U in FUD stands for. The way they resolved it is much better.