No it is not gear lube for the rear bearing, it is as Corey state. As for moly or not. If the grease is rated for wheel bearings it should be OK. You have tested it out on the front wheel bearing, and it should be all OK. Many Moly fortified greases are rated for Wheel bearing these days.
In the past, the moly was not small enough in the formulas and it could cause the roller bearing to seize on the race for just a moment. Then over time, the roller would get a flat spot and take out the race.