Vec
Even if your last statement were true, your post acknowledges the possibility of these uncleared nav kits being inaccurate/faulty/defective etc.
MoD's case is built on them being fully serviceable (they were not) and able to be used in the final moments (one was switched off).
That rather proves the point of those whose sole aim is overturn the verdict. There may have been poor airmanship. That there was prior negligence does not make you wrong. The difference is that this prior negligence is demonstrable fact.