Rengar's Empowered Battle Roar Removes Tahm Kench Devour?

My understanding of these abilities are that Tahm Kench's Devour (when used on an enemy champ) suppresses the target for the duration and that Rengar's empowered Battle Roar is a cleanse, that is, it removes crowd control but not suppression. My last game I played this matchup and it definitely was not the case. Rengar regularly cast an empowered W to escape Tahm's W.