After reading your post, I believe you and your uncle are correct with a front should, brisket muscle hit. I am assuming the arrow had very little if any penetration. I recommend that you continue the search for you deer by widening your circles. As we all know, deer are very strong and resourceful. I am guessing that your deer will make it to see another day. Keep an eye out for coyotes, crows, etc they may point you in the right direction if the deer does bleed out. The only thing you can do is give it a 110% effort on retreiving the animal and hope for the best. Just my two cents - Good Luck - Soup