sorry man that really sucks. if you have not done this & if you do go back do radius search where the track or blood was last found. work your way starting close then circle around. if that does not work check & walk all the main trails. they are creatures of habit. some of my friends had suggested to look for water cause the deer will go there to drink when wounded. if there mountain lion tracks it's good chance it took it. because they smell the blood for miles. another good trick is get a spray bottle fill it full of hydrogen peroxide, & spray near where the last blood trail was because even a minute amount of not visible blood will bubble & fizz.. check the leaves good cause they flip over. try not to walk on the trail. because it destroy possible minute blood spots. Use tape markers to locate each blood spot found. I hope this helps as suggestions. if you have done all this and more then you have done every thing possible. and it happens to the best of us. don't give up.however two miles is a long tracking and it is possible it's a flesh wound. good placement shot & that deer should not have gone more than 150 yards.