Something is not right here
These folks are truly experts and immensely experienced. They expressed no doubts as to the origin of the Pings, which occurred where, obviously, they expected them to occur. Now they all believe the Pings were not from 370 and that is the reason for not releasing the recordings. I'm not much into conspiracy theories but something very odd has happened here.
Pretty sure nothing in nature makes 37.5 kHz pulses lasting 10 ms on 1 second intervals. Also pretty sure no other planes had crashed there in the past month. That means someone threw a pinger into the water.
For all those people who were uncomfortable with the idea that a group of Chinese on a rubber raft with a fish finder on a pole could have found the signal, you may have your answer now.