Originally Posted by JamesNoBrakes

Something doesn’t add up here, flying the ILS has nothing to do with Va. Va, Vb Vc, Vd are all design speeds that take into account certain gusts, if it was extremely turbulent, it might be plausible that you should be less than Va, but that would a) be pretty damn turbulent and b) apply to any phase of flight, not just the ILS.

Ask the examiner what area of operation, task and skill you failed. Tell him you are having trouble figuring this out. Call the FSDO and ask to speak to the DPE manager and keep elevating this until it’s solved. You won’t get in trouble or anything for doing so.

This assumes you didn’t fail for failure to control airspeed as described in the task, but it should be understood that the ILS usually includes different speeds and configurations at different points. Usually competent schools and instructors have specific profiles to fly for approaches, giving the target speeds.