Roch out of curiosity. What donut told you these runs of blood were injuries and thus it was proof of Sheila's involvement? 
They are injuries and I have offered to bet money on it (precisely because I know they are injuries).
Blood is not going to transfer to her hand one second and then dry and collect the very next second approximately two to three inches from where it transferred. Nobody has satisfactorily explained how it transferred. Not even Vanezis. He bluffed it out.
The dark spots at various places on her arm are not the end of blood trails. They are the source.
Consider this, she has cuts to the skin on her upper arm which are completely independent of any run, trail or smear. How likely is it that she has cuts to her upper arm but the marks on her mid and lower arm are merely where the blood has suddenly stopped and become congealed as it dries? She has other wounds also - not even mentioned on here. Besides, I don't believe you and others couldn't recognise the gouge/scrapes on the back of her hand or the angled cut on her lower forefinger.