You know how sources and their relative veracity work right?
The only 'new information' in the 2019 article is the UCLA grad student bro who listened to a recording sound and said 'crickets' and then professor from Edinbraugh and one from Havana who disagree with the initial study findings.
And a Harvard guy who says that no one has actually seen the raw data, probably because it is classified. The only doctor who examined the people affected maintains that they were damaged. And none of that explains the same phenomena and injuries against the same tiny subset of people, the American Foreign Service, in China half a world away.