Lu, it's impossible to answer your question authoritatively based on what you've presented. It is possible that a brake at one end of a shaft that is driven or has rotational kinetic energy from the other end could cause the shaft to fail, but that is only one possibility.
To simplify a complex matter, for anything to break, the brake must be able to exert a torque that is greater than the weakest link. For your proposition to be valid, the brake must be strong enough, the energy must be high enough, and the shafts must be the weakest link in the chain.
From what I understand, the rotor brake of the EH101 has been changed during development. Is your information current?