Pat, the emerald ash borer does penetrate the wood beyond the cambium, although it usually doesn't go more than an inch or two in. Regardless, THE WOOD SHOULD NOT BE USED, PERIOD! BURN IT!!!
Ash wood is excellent firewood, although the BTU value is not as high as oak or hickory. If used for firewood, it should not be transported more than a short distance from where the tree died. Firewood seems to be the main vector for the spread of the bugs. In Missouri, the borers were found first at a campground, where it is thought that someone brought infected firewood from one of the quarantined areas.
If someone builds a bow from infected wood, carries it to a shoot somewhere, breaks the bow and leaves it behind, that person could be responsible for spreading the bugs. Don't do it!
Heat will kill the grubs in the wood. The wood has to be heated to about 170 degrees F at the core for a half hour or more to kill them. Currently all ash wood from the quarantined areas must be heat-treated or fumigated and documented under a USDA program before it can be transported out of the quarantined areas.