I mean, they have chinese money in basically unlimited supply, if they pump the esports full with money, there will always be takers for the money.
Sure, if the game itself fails they have a problem but I dont see that happening
Riot has a huge budget for shills and marketing. They also know how to turn the average fifteen year old player into an addict, queueing a game after another. Only thing that can happen is them fucking the game's balance so much people are turned off, but the addicts will still play