It gets it's randomness from a hardware random number generator that uses thermal gradients to produce entropy.
I guess that is exactly what he is afraid of.
All these hardware random number generators are completely unauditable - its even worse than with the software.
Unauditable? Check this tool out:
http://www.phy.duke.edu/~rgb/General/dieharder.phpThe RNG in Piper has passed all 26 tests in that program that have a rating of "good". The "good" thing is because the developer also includes tests that are questionable, so we only tested Piper on the ones he rates as "good". Here are the results:
http://piperwallet.com/dieharder-results.txtSo the RNG in Piper has in fact been statistically audited for secure randomness and passed all tests to prove it. I store my own coins in Piper and I wouldn't feel safe accepting anything less than that.