So, according to Ivern, Kumungu still exists in the lore

"Brambleback, remember the Kumungu affair? I still think it was your fault."

Just in case it was previously doubtful, this line towards the Brambleback confirms that the Kumungu jungle still exists.

######And yeah, I know this might have been somewhat-expected since Bioluminescence said that there's at least one big jungle in the updated Runeterra (or something like that). Still, it's nice to see it confirmed by a champion.