Seems dangerous to infer too much about the general behavior of entire species based on the observed behavior captured in two individuals at the moment they were being entombed in the lava flow from a volcanic eruption.
Like assuming that based on some skeletons found under a volcanic ash flow that the normal behavior of humans was running with your hands in the air and screaming really loudly.
This single group of humans almost always assumed the fetal position. Fortunately we were able to get a glimpse of this because they were captured in a lava flow. We may never know why they did that.
It was a mud flow. It likely came on extremely fast while they were distracted by their life and death struggle, and not necessarily during a dramatic eruption.
Additionally, it's a pretty solid prior to assume that, when we find rapidly forming fossils like this, the behaviors they capture were common behaviors. Fossil formation is rare, so a fossil capturing a rare behavior is pretty darn unlikely. A behavior would have to be ellicted many, many times to have a likely chance of being preserved in a fossil.
Surely they exist, and this could be one of them, but until we find evidence to the contrary our best guess should be that this was a common behavior.
Like assuming that based on some skeletons found under a volcanic ash flow that the normal behavior of humans was running with your hands in the air and screaming really loudly.