In isolation, I might have said that spike is due to a cloud-edge effect, where the edge of a cloud acts like a lens, creating a temporary, dramatic spike. But, based on the nearby production curve, I am guessing there was no cloud. The dip to me looks like what you might see if you had a brief fault knocking your system off line for a few minutes.
Did you happen to see this unfold real-time? That is, did you happen to see the spike in the graph before the dip appeared? As strange as it would be, one other possibility is this is just a data issue and Tesla somehow recorded that production data to the wrong time. It seems like the magnitude of the spike roughly matches the dip, and it would explain numbers that seem well beyond the capacity of your inverter.