Yes you don't need to put the egg in if you are careful to make a dry meat ball, i prefer a moist meat loaf and will add a cup of stock to a couple of pounds of meat loaf, but the loaf is baked in a pan, the meat balls have to be a little drier & firmer to hold their shape while you pan fry them, wine, soy sauce, stock to moisten and flavour all according to taste.
Probably no more than a few tablespoons of cream, you can even soak your bead crumbs in cream or milk or other liquid and squeeze most of the liquid out and add, or use just enough oat bran, crackers, bread crumbs or whatever for flavour rather than to extend the meat which is why the recipes call for them.
Often times meat balls are made with out any extender at all merely flavoured.
I just happen to like the taste a bit of oats or seasoned bread crumbs add to the taste.
The simplest way would be to just lightly season the turkey meat balls and pan fry them. Served as meatballs it would probably be good to try to get a bit of browning of the outside of the meat ball, crisp it up a bit, not only will improve flavour but appearance also.
Due to my fondness for the Rodale cook book i often make turkey meat balls and serve with a yoghurt cucumber dipping sauce. --- JL