Crime Scene Investigation. One letter short of NASA :)
Visited Wind Cave nat’l monument in SD last month – lots of entrances, some small, some very large. Over time, some collapsed, some didn’t. I visited caves in the south central area of France as a kid, and the influx of water was such that you could watch a foot of growth for every 5 minutes (i looked like a powdered donut afterwards). Most caves found in that area were through obscure entrances when the main entrance was covered by landslides…. there’s a nice movie about a spectacular cave find on Netflix that is worth watching (french with english subs).

I hate acronyms. What does “CSI” mean?

I was not implying a weird alien cause for their location in the cave. Your guess is reasonable, but since we do not know the condition of the remains in the cave it is difficult to theorize. As a caver however I must tell you that entering by the present access through the chute is far from trivial. Falling in is impossible for several reasons: You wouldn’t fall, too small. Second, according to the map at the link the remains were found on the opposite side of the room from the bottom of the chute.

As for having an old entrance blocked by a landslide, that might also be true but it is unlikely. Caves are very stable, having been formed over a very long time by water processes.

Perhaps there was another entrance to the chamber in prehistoric times. The structure known as “the Dragon’s back” may have been suspended from the ceiling in the past and it fell, closing off a passage similar to “superman’s crawl”.
Apparently there was a large amount of debris in the cave that had to be removed to access the first chamber as indicated by the red line denoting the level of the “flowstone cap on red mud”. There may still be an undiscovered lower entrance.

Or maybe their funeral rites entailed placing the dead in the top of the chute and decomposition carried them into the lower chamber.

I’m always a little surprised when homo sapiens find it difficult to envision that sapiens are the only possible species within the genus homo. The fossil record tells a different story.

Not every event in the past has to have a CSI answer :-)