Petrov [Phys. Rev. E 111, 035205 (2025)] has presented explanation of some parameters of terrestrial gamma-ray flashes within the framework of his model which is based on the assumptions about the formation of surface plasmon waves and generation of synchrotron radiation due to the interaction of these waves with the electric field associated with the lightning channel. Here it is shown that this explanation involves the mistaken use of equations, describing generation of synchrotron radiation by electron. Namely, the velocity of the surface plasmon wave is substituted into these equations instead of the velocity of electron.