I am watching a lab pit mix help?

Sounds like he is acting like a puppy with no particular manners. I am wondering if the "attack" was more like a rough dog play? Can you get or borrow a dog cage? Then he can stay in there for part of the time and give you a break. Or, tie him to the kitchen table for brief periods as long as your dog won't take advantage of him. A cage would be the best alternative. Try garage sales if you don't have one. Put a leash on him in the house and make him sit for you.