The headline here has no mention of wet bulb?

“For the first time, humans were subjected to a deadly combination of heat and humidity.”

The article is about the first formalized test measuring the relationship between heat and humidity on thermal management in the body, mostly using a single fit thirty year old male. It’s not about how the first human subjected to wet bulb conditions handled them, but about an improved understanding of the relationship of heat and humidity on thermal management of humans.