There was a time I was familiar with both codebases (I have some catching up to do) and that's why I mentioned them. Both projects carry heavy heritage and are experiencing huge pressures to evolve and both are doing very well (from what I hear on the dev lists).
That doesn't imply that they are being successfully maintained because they are written in dynamic languages, or despite being written in dynamic languages. And of course there's also the possibility that static vs. dynamic is a wash and doesn't really have an impact at all. Or that the potential impact of going with static or dynamic is heavily influenced by other factors - does the static language have type inference, does the dynamic language support duck typing, stuff like that.
Long story short, correlation does not, in and of itself, imply causation.
Heck, the examples you give aren't even anecdotes. They're just name-dropping. One would have to be pretty familiar with the codebases in question and the history of their development in order to be able to give a clear assessment of what, if any, impact dynamic typing might have had on them.