Hello: I can give you a partial answer. It looks like you have a six year warranty on your tank, but I’m guessing from numbers that don’t quite line up. If so, it likely has only one anode, which you probably will see as a flat hex head on top of the heater. That eliminates any confusion about mixing powered and sacrificial anodes, (which you don’t want to do). The powered anode rod is a much more certain fix for odor than a zinc/aluminum sacrificial rod.
Also, there is a discussion of odor in tanklets: http://www.waterheaterrescue.com/pages/WHRpages/English/Troubleshooting/Tanklets/water-heater-odor.html