Tahm Kench + Cassiopeia Bug

Recently, while playing ARAM my Zyra's model completely froze. I know it's quite cold on Howling Abyss but I investigated it further and it turned out that it's an interaction between Cassiopeia's stun and Tahm Kench's devour. I had some fun with my friends and we managed to reproduce this bug many times with different champions.

This bug doesn't appear on the replays and I recorded it with my phone just to show what's going on.

We encountered it on EUNE, we didn't check any other server. All players in the game saw it. I was unable to use emotes and champion's emotes. Fortunately during this first game I didn't try recall animation because it sometimes gets even worse after this like Qiyana got invisible almost completely (she was still targetable tho). Death doesn't reset this bug but Neeko's passive and Sylas' ult do. We managed to reproduce this bug only on Howling Abyss, we tried to do it on Summoner's Rift but we failed, we are still not sure if it does'n work or we tried wrong champions. We failed to reproduce this bug on Fiddlesticks and Cassiopeia, maybe because they are older?

I reported it to Riot Support on Twitter and they suggested I should add a post here too.