Don't worry about the lack of adjuster bolts. The holes in the dropout for those bolts are a common failure point. Position the axle in the slot wherever you find that it optimizes shifting. Tighten the quick release or axle bolts properly, and the wheel won't move in the slot. The adjuster bolts were for racers, to facilitate quick wheel changes in a race where you have mechanics and spare wheels along to quickly swap things out. If that's not you, you're not missing anything by not having those bolts.