I might be missing something, but I don’t know an easy way to get the userIDs of other users.
The best way I found so far is to use the competition match data results, since there are userIDs included: https://terminal.c1games.com/api/game/competition/135/matches
Do you know any other way to get them?
I think this userID could be something you could also add to the leaderboard api results: https://terminal.c1games.com/api/game/leaderboard?page=1&season=5&limit=10
Currently the userName is included but not the userID