If you still have the stomp starter, and you have good connections to it from the battery, it should turn the engine over whether any thing else works or not. If it won't even grunt, then the problem is between the battery and the starter or the grounds.
Since every thing else powers off the positive cable at the starter, my bet is the cable from the starter to the battery (+) is bad some where. Place your meter with the + lead on the cable at the starter, and the ground lead to the engine, and have some one step on the stater, the voltage will likely die.
I found one time where the braided cable mounts to the frame had rust under it, and then the cable from the frame to the engine also had rust. The guy had about pulled his hair out trying to find the bad connection. Cleaned those and it started up.
Last edited by Roy Rodgers; 04/16/2014 1:24 AM.