Any 747 operator able to back-calculate the approximate rotate point from brakes-off assuming that 2700m of RW had been planned in the conditions prevailing?
If the a/c really did enter the RW at Taxiway Delta, why did the tower not query it? The Delta entrance is almost directly outside the tower window.
I once flew a simulator sortie from Colorado Springs at MRTOW and the 'modelled' RW on the visual was the older RW, whereas we'd planned the newer, longer RW and had been re-pos'd at the holding point to save time. When you see the end of the RW unexpectedly rushing towards you between V1 and Vr, it's quite horrifying even in a simulator. What would you do for real? Well, an RAF TriStar was once confronted by an idiot army driver in a truck who'd crossed the RW without clearance - and by going to max thrust and rotating well below Vr they cleared the truck (just) but I can't recall whether the tail struck the RW.
My condolences to the bereaved.