Zhonghong's stake in Seaworld cost them over $400 million in 2017. They just defaulted on $174 million in bonds. Yeah, doesn't look good for Zhonghong. And yeah, they could raise the cash by selling off all or part of their 22% stake in Seaworld (they could theoretically sell off a quarter of the stake to raise the cash and still maintain control of the board). The issue is ... who is going to buy it? Six Flags' has about $68 mill in cash on hand and another $230 mill or so they can borrow against in a credit facility. Cedar Fair has more - $145 mill or so in cash for investing and another $160 mill or so they can get ahold of by financing it (they have a credit facility, but only for operations, not financing). Even if Zhonghong wants to take a 50% loss in valuation on that stake - which they most likely wouldn't want to do unless absolutely necessary - neither SF or CF is in a position to buy it. I'm sure the management groups of all three parks are in contact though, as that's common industry practice. Portfolio managers routinely check in on companies that are on their watch lists. It could easily be a twice-yearly visit from SF triggered a rumor and some admin ran with it. Stranger things have happened.
As for the article, most large papers don't actually employ regular journos other than editors and big-name feature writers. They largely rely on freelancers who get a lot of their information much the same way we do - scraping through internet forums, Facebook groups, reddit subs and other places insiders are wont to post about their jobs. The piece itself is pretty innocuous if not exactly rooted in reality for the reasons listed above, but it's not exactly what the Columbia J-School would label "good journalism" ... or really, "journalism".