[Gameplay] Cassiopeia Miasma (W) Bugged

Just came from a Summoner's Rift match where the enemy team's Cassiopeia's Miasma AoE would not show on the ground for me or my team members. This was the match in question (http://matchhistory.na.leagueoflegends.com/en/#match-details/NA1/1868968773/37937062). The animation for her Miasma played as it normally would, but nothing would spawn on the ground. The Cassiopeia player informed me that she could see it in her game. It was only my team that did not see the effect. This was strictly her W, all other abilities appeared to be working as per usual. The match history is all I can provide since, well the effect is invisible...