After disassembling the two Launch Pad Controllers that stopped working I was able to determine that there is no battery problem. The test boxes use a different power switch than the ones on the current system; one that comes with a plug-in harness with pigtail wires to connect the battery to the system. The switches seem to be fine but the connectors in the harness are crap! I'll need to wire it without the supplied harness. This is a truly insignificant issue to fix.
I don't yet know what caused the one hangup but I'll be tearing into that once the power issue is resolved.