No, I think they are referring to tired light hypotheses generically and excluding them all. They just use Zwicky's as a convenient handle. Check the wording "interact with matter and other photons in a static universe". That's pretty vague, not what Zwicky said. All you have to concede is that it is possible that a tired light mechanism can possibly arise which predicts time dilation too. Is this so hard? It seems it was hard for the authors of the article, but you too?