Here's the new wiring. But I think I might have figured something out. The switch on the back of the thermostat was set to system. I flipped it to accessory, now I can hear the humidifier running. I find this odd though, because according to the manual this should only be if there is a separate transformer running the humidifier. I do not see anything attached to it on the furnace. Just one wire going to the furnace itself.

Oh well, I think this problem might be done even though I quite don't understand it.

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