I had time to waste, so I watched the actual presentation the slide come from, and they admit they don't know where the transaction come from: https://youtu.be/dyyA0YjSslU?si=Cnm60dS_rA0q_Yd_&t=33m44s
At the Q&A, they also admit they can't monitor transactions of other nodes, all they do is just try to know who is behind a node.
It looks more like a compliance tool than a monitoring tool.