“He might have been running away since he was hit in the back”
Not enough evidence to make any conclusion.
He could have been sitting at a campfire or taking a leak when he was hit by the arrow. He may have been pursueing one attacker when another outflanked him. There are an infinate number of scenarios.
Yep—that’s why I wrote “might.” Thanks for your comment, though, as additional scenarios help keep everyone’s mind open.