I doubt that the lack of a bungie between the leg straps is what caused this accident. Although, it may have prevented it.
But here's what I'm curious about....
Canopy = sub-100 (let's say 96, since we don't have the actual size)
Wing Loading = 1.6
That puts the persons actual exit weight at about 153. Subtract the rig weight of about 15 lbs, leaves you with a person who weighs 138 lbs.
That's a pretty small person, wouldn't you say? I'm hoping that the rig this person was jumping was custom built for that type of person. If this very light-weight person is jumping a rig that was bought used, it may have been the actuall size of the leg straps (too big) that may have caused this mishap and not the lack of a bungie.
Unless of course your figures are incorrect.
-Jonathan