Sorry you don't find my statements logical grounded.
I don't understand your statement about certification. The basis of certification I believe is the TSO and that is quite clear on the matter. Irrespective of aircraft.
I will repeat, in my experience, a Radalt will flag data as NCD whenever in Search mode (after mem has timed out.) This can be caused by many things, not just altitude. Speed may not be a direct cause, but is part of the set of causal factors, particularly during manouevre. So to say whether a radalt will go NCD is not always straight forward. The specification tells us when it won't under normal conditions. That is why the velocities are stated in the specification.
Is tracking capability "groundspeed", No. Is it "vertical speed", Not exactly. What will happen outside this limit of 330 ft/s. Outside the certification limits the accuracy is not guaranteed to be as per specification.
Grounded, you clearly have more detailed knowledge about this unit in particular so that is where I will leave it.