The only way I could imagine that working would be makeing it waterlevel depended. So ones the level is reached, the pump turns on. But FL'S don't use a 1-level sensor, so the direct connection is out of the way.
Next, he could have coupled it to the door-look. But than, it would run througout the cycle.
Next, he could have connected it to the waterinlet valves. But again, it would run throughout the spins.
Next, he could use kind of switch that turns the recirc of in the moment the drainpum turns on. I don't know the exactly spincycle configuration, but if it does any spin-part (redistribution or as LG during spin) with the pump turned of, this would work not again.
So, I think he used one switch that allows the current to flow as long as the door is shut, one that stops the current as the valves are powered and one that does the same for the pump. Than, only the fillstage would cause to low waterlevel for the pump not to work, and as this phase is rather short, it wouldn't mean any damage to the pump. And the current is pulled from the main power cord. Could this work?