...maybe your better half doesn't like your growing? is there a possibility of sabotage? or maybe the watering can wasn't clean and something mistakenly was watered ON the leaves... i suspect that the plants were incorrectly watered i.e. watered on top of leaves vs the soil directly...and then there may have been something in the water.
we have some nasty invasive bamboo, and lots of poison ivy. in the warmer months, i make a mix of salt water, like 200% salinity, and spray that directly on leaves and sure enough after a couple of days, the leaves look similar to your pictures.
regardless of what happened, the best course of action for saving this would be to cut off all damaged leaves, and see what you're left with. is it worth saving? honestly after only 30 days in, i'd just restart with new beans, if you have them of course.