Mimicking a Talmid Chochom is decidedly distinct from ch’vsh being mevazeh one. Of course, each case is difference, and one person’s harmless Purim shpiel is another’s spilling blood. But the tradition of mimicking one’s rebbeim, especially on Purim, in a fond, non offensive manner, is well established. Although of course due caution should be taken with so serious a risk. And copying and making fun of are two different things.
On a minor further note, by a happy coincidence I was present at the event mentioned in the OP. Yekke2 has done well to camouflage some of the details and ensure anonymity for all involved. but as a witness, I personally cannot really understand yekke2’s quandary, as by all accounts his actions were suitable to the occasion, and to the to my eyes undoubted slight against the Talmid Chochom concerned. But I would have to read through the thread more thoroughly before I could profess anything other than almost complete ignorance.