so just like some of you I myself can no longer install league of legends due to updating to Catalina. Now I happen to be a programmer and I was very intrigued by the fact that the game worked for existing users, but not for new installs. (https://euw.leagueoflegends.com/en/news/riot-games/announcements/new-mac-installs-possibly-halted-macos-1015). So I had to find out why.
After some digging I found out that it is not the game itself that has a problem(logically since it runs for existing users). The game itself is 64 bit which is supported by Catalina. So what is happening?
Well it turns out the installer of the game is not working properly, this is due to the installer being 32 bit (which is not supported by Catalina, for admittedly good reasons but certainly not user friendly in the slightest). Therefore the solution is to make a 64 bit installer, this will allow the game to be installed on Catalina thus solving the problem for new players.
EDIT: I do understand that if there are a lot of 32bit dependencies in your installer it might not be an easy task, but please be transparent if this is the case.
EDIT 2: I have since downgraded and am playing again buuuuut, I know must people do not know how to make an installation disk or use the command line, so on behalf of those people a simpler solution is needed.
EDIT 3: It seems your patcher is also 32 bit as well as your repair tool, so your claim that it works and will continue to to work for everyone with league installed is false, which is worrying.
Now I know this is not top priority, but I just want to tell you that gamers on Mac do exist and I would really like to continue playing league. Its ok if it takes a few weeks to make a 64bit installer but please do not leave us in the dark.
We just wanna go onto the rift.
tldr; The problem is not with the game but with the installer, create a 64bit installer and you solve the problem.