We don't know they didn't say that. We only have what appears to be an excerpt that is missing a ton of context.
At this point we can't rule out that the employee cut the most damning part of an email out of context, put it in the commit message, and submitted this post on HN themselves (it's posted by a throwaway, so it's likely someone intimately involved in the case, not someone who just stumbled across it).
That is certainly a possibility, but if the quoted text is quoted verbatim, the way it is worded doesn't really feel like there was much more context. But that's just a guess on my end, and I'm relying on the assumption it was quoted unmodified.
That said, fundamentally, the question is whether you trust in Lijun Pan to represent the situation without distorting it. Without evidence to the contrary my personal assumption is to start with a little "trust credit" and take it as it is — for now…
At this point we can't rule out that the employee cut the most damning part of an email out of context, put it in the commit message, and submitted this post on HN themselves (it's posted by a throwaway, so it's likely someone intimately involved in the case, not someone who just stumbled across it).