Wow! This is the first time I see this thread and, first of all let me say that it is absolutely NO coincidence that he wandered up to YOUR car. How many people would pull over and pick up up a scraggly-looking, bloody, beaten up, sad-sack dog (I mean, except all of us on this board)?
Secondly, go back to the first few pix you took of him and look at those last ones. You can tell how much better he is feeling. The poor thing looked so sad, sick, nervous and scared in the first pix and now he's beaming with happiness and gratitude. He looks like a completely different dog!!
Huge kudos to you and your family. I know when you have so many critters at home it's easy to say, "what's one more for a little while," but it really does put a strain on your "keepers" and the family - especially when the foster needs so much extra attention. You earned your wings again!!