Really surprised no one has made this suggestion by now. Why not just remove the geodes from the treasure pool for the chigoes in question? Going to assume that if they crit kill, since that makes it not yield exp, that that means no credit for the trial (just guessing, idk for sure). So it makes sense to follow that no trial credit and no geodes equates to no more summoners out there. And even if it still gives credit for trial, I'm sure that would, at the very least, get rid of the RMT bots out there.