Bill, well I must be in the olden days, because my guys favorite thing right now is a burlap sack tied to the end of a rope lol!
The best thing to do is stick with your trainer's program. If I was a trainer it would be exasperating to have a "student" going on forums and trying to get ideas from who know's who, that don't know your dog, and getting advice. Your trainer may want your to focus more on building the dog's confidence right now.
Stop throwing the ball....ball leaves your hand, dog takes off = no interaction with you. Talk to your trainer about a bitework harness, back tying, and teasing. Tease the dog while it's in it's crate....start small in places where the dog displays attention and ignores distraction (at home or in backyard). Make sure you balance between teasing and allowing a grip/win....too many grips, game isn't as fun, too few, the dog doesn't believe he'll get it and he may not try as hard. However, talk to your trainer about all this. What did he tell you that you should be doing at home?
How's the dog's food drive in different areas (some people think their dog has amazing food/ball drive, but then they take the dog to a new area, outside the home, and the dog could care less about food or toy)??