You're 100% sure it's a school of crappie? Reminds me of a ball of shad, but maybe you can see better in real life versus a video.
Years ago (before kids) I would net a few shad some evenings for catfish bait. We would look for surface activity similar to what your video shows and throw a cast net over the school. Never caught a crappie or anything else while tossing the cast net, just shad, and lots of them.
Outside of the crappie spawn, when they are shallow, all my crappie fishing is done either trolling or on deep structure. We also sometimes "spider rig", kind of... There is a 2 pole limit in KS unless you buy an additional permit for a 3rd pole, so our "spiders" are lacking legs.