I'm not sure I understand your point? Attorneys generally follow the money and sue everybody involved. If Peyton brings suit, his attorneys likely will pursue multiple causes of action. He seems to have an actionable case.
My last post on the topic, so I don't Bruin this thread:
My points are:
1. It's difficult to sue news media, especially for celebrities.
2. Sly backtracking isn't enough to make it a case, because the retraction could be self-serving.
1+2= The case likely wouldn't survive summary judgment.
Look up Latrell Sprewell's case vs. the NY Post, if you don't believe me. The Court in that case said, basically, that the standard you quoted boiled down to whether the reporter knew that the articles were false. The fact that the Post attributed the statements to "sources" also made a difference.
In this situation, how is Manning going to prove that Al Jazeera knew Sly's statements were false? Because he changed his story once it got out? It's arguably a self-serving retraction. No unbiased judge is going to say that's enough to satisfy that standard.
Then you get into issue of the the semantics of the article and most trained reporters are smart enough to write a libel-proof article.
Sly should have known whether the statements were false and it looks like he made factual statements about Manning's use of HGH; that's why there's a case against him. As you say, he doesn't have enough money to be an appealing target.
It's not a good case and people here only think it is because it's Peyton Manning.