Having an issue where the leaves are spotting Brow...

Based on your last pictures I think you're over-watering your plants. This could also explain why those spots appeared after spraying : roots are already overloaded of water, your leaves can't absorb anything event tiny drops, then your light turns on while leaves are still wet : burn holes appears. I would stop spraying anything unless it's really necessary (spiders treatments or leaf protection layer..), let the soil dry for a couple of days, then remove the dead leaves and see how it goes. I'll be around, good luck with these babies!

Those brown spots do look like they were caused by droplets burning off from you lights to me also. I don’t mist my plants as often as you, but when I do I mist at the beginning of the dark cycle so the moisture has evaporated before the lights come back on.