Without experimental data to back it up (e.g. implementation and benchmarks), I'd consider this claim veeeery dubious - regardless of who it came from.

Extraordinary claims need extraordinary evidence, and in this case it would be easy to provide such evidence - by cracking appropriately-sized challenge primes in a transparent way that can be independently verified.

On the other hand, the theoretical approach in the paper is quite complex and hard to follow - even for professional cryptographers.