That or maybe run away to where you know you aren't being chased and try waiting 48 hours. Something like this happened to me with Galmar Stone Fist of the Stormcloaks, where I didn't have the option to ask for a quest when the arrow was right above him. That's all well and good, NPCs that bug out can expect an ass whoopin'. I just ended up running away after since he kept getting back up, waited for a while, went back, and dude forgot all about it.