Regarding the Oxford-Shakespeare debate, the article didn't give any hard evidence because there isn't any hard evidence, for either side. In reality, the only evidence there is for the Stratford man having written the plays attributed to him is because they were attributed to him in the first place. The lack of evidence for Shakespeare is appalling. Oxford at least has circumstantial evidence, and the doctoral dissertation recently written about Oxford's possible authorship gives pretty strong evidence with the comparison of Oxford's bible to the plays. I'm an Oxford supporter myself.
As for Welles, in This is Orson Welles, while discussing the Bard with Bogdanovich, he mentions how Shakespeare was a country man, and from the lower class and so on, so he was clearly not talking about Oxford in that case, which was a good number of years later. Why not mention Oxford there? Maybe he didn't want to get into it in that context. In the research materials for Five Kings at the Lilly Library, there is a pamphlet about the case for Oxford, so Welles was certainly aware of it from early on. Roger Hill even mocked the Oxford case in Everybody's Shakespeare, which goes back even further.
I would recommend checking out the Times article, though. You can find it
here. It's a fascinating story if nothing else.