You can take its license plate down, record its VIN, take a few pics, etc.
The shooter claimed to see the owners of the drone show up, park, and launch it, and you are telling me it's 100% impossible for her to find the license plate of the car she saw? Walk up to it while it was there and write down the license plate?
How does that work? It moves faster than you, and isn't limited to passable terrain, fences, creeks, rivers, buildings...
Why does your need for revenge trump the rights of everyone else?