You're thinking of manual strangulation, but this was ligature strangulation and she did have extensive petechial hemorrhaging on the insides of her eyelids.
My understanding, correct me if I'm wrong, is that death BY strangulation is uniquely determined ONLY by patechial hemorrhaging of the WHITE area of the eyes and not the eyelids. THAT kind of hemorrhaging can be caused by other factors. That's how I read it (I think the Mayo clinic website).
BTW, are you saying that manual strangulation produces a different pattern of patechial hemorrhaging than a ligature? If I'm reading that right, that's odd. Not knowing either way I'll go with that for now.