My bias would be no, the cable won’t make that much difference. Of course, until you try it, we can’t know for sure...Can you by an expensive quality cable with a return policy? Even if there is a restocking fee? At least that way you would satisfy you curiosity.
Does your Cambridge amp have a usb input? If so have you tried comparing the phone without the Wadia plugged directly into the amp/DAC? That would remove the Wadia from the equation.
Does your Cambridge amp have a usb input? If so have you tried comparing the phone without the Wadia plugged directly into the amp/DAC? That would remove the Wadia from the equation.