I think u are being way too rough here. If anything Vespi checks Mime better than that weird ass Oranguru lol. It doesnt need attack order to be a check as mime can be pp stalled by pressure unless psychic doesnt get spdef drops.did u forget the point of two bug moves..? and that too by sacrificing its imp moves...? at this point you might as well use sash flail magikarp tbh lol (I know sash is ban, but you get the idea what I am trying to say right..?) furthermore 0.4% chance is by no means equal to 0% chance isn't it...?
252 SpA Choice Specs Mr. Mime Psychic vs. 252 HP / 252+ SpD Vespiquen: 130-154 (37.7 - 44.7%) -- guaranteed 3HKO
Also 0.4% its almost never going to happen and even less twice in a row so even if locked in M-fire u are good to go.