Cazatou
The equipment is practically self contained and intrinsically accurate and reliable - like sticking a GPS on your car windscreen and plugging it into the lighter - if they thought they were 1/2 mile or so further out then how can you say that they were approaching too fast? - the dist/time calcs (remember the increased tailwind component as they neared the landmass) and engine state indicate that they had started to slow down.
The sets of such equipment delivered in early 1995 were designed to be easily transferred between HC2 Chinooks - how would your formal certification apply to such kit?