They clearly know it, but they clearly have lawyers that are wise enough to see that lawsuits are one of the few things Musk can still generate. Otherwise they could have written a much shorter article:

Alp Toker, director of Netblocks, said the social media platform’s explanation of how the issue was fixed “isn’t particularly consistent” with a DDoS attack. “Given Elon Musk’s claim that X had to limit the number of live listeners to mitigate the issue, we can infer that the outage correlated to the number of live listeners,” said Mr Toker. “Limiting the number of legitimate users isn’t an ordinary mitigation for DDoS attacks and wouldn’t usually help… so Mr Musk’s own statement suggests that the platform might have been struggling with overall listener capacity.”

https://www.google.com/search?q=elon+musk+firing+twitter+engineers

🤣