Everything that Ventor says is correct. He didn't need to quibble about the universality of the genetic code but it's true that there are variants.
His point about the tree of life is correct, especially in a discussion about the origin of life. It's unfortunate that Richard Dawkins repeatedly makes such an issue about the tree of life because he's on shakey ground when he does that. I assume that Dawkins hasn't studied the problem. However, he's in good company since most scientists don't understand the problems with the early tree of life. The early history of life looks more like a bush with many interconnecting branches due to horizontal gene transfer [The Tree of Life].