OK, I can confirm that these things just don’t work. I have one connected to the lowest noise MCU I could find, an Arduino powered by a battery. The thing is on a post in the middle of a field, more than 800m from any interfering electronics. We just had a heavy thunderstorm go right over our heads. Constant lightning strikes all around, one even struck one of my neighbors trees.
My AS3935 (clone) detected - absolutely nothing except some noise 
Maybe it’s the clones that are just broken, I don’t know.
For reference, that is the thing that went over us. If the AS can’t even detect something like this, I don’t know what will make it trigger…
(From https://map.blitzortung.org)