Here is a short video of caver Rick Hunter squeezing through one of the tunnels to the Dinaledi Chamber. Not for the claustrophobic.
https://www.youtube.com/watch?v=fTPRx8xVafE
Just last week, while riding to the airport we went through a large and long tunnel. I suddenly felt trapped (a first), and then my brain got confused by the lack of light thinking the black 'ceiling' was a night open sky. I imagine being in a cave might trigger similar sensations.
How on earth he got through that gap I'll never know