I don’t suppose you will ever respond to the core point made in the quote you offer from my original critique, that the values in your equation 4 refer to experimentally observed data, whereas those in equation 5 apply to all and any velocity whatever (including the observed velocity). Despite that, you still assert that ONLY the observed velocity can fit equation 5.
The argument is the same as that if that dog is called Fido, then all dogs must be Fido.