I am making a competitive platform where dota tournaments would be held. I went through the OpenDota api. It does not allow us to make post requests to create a lobby, a match or a league etc. I looked into other competitive platforms like Challengermode.com and FACEIT.com where you can link your steam account and create games there. Then It would open the game at designated time and user plays it. These platforms most likely have been sponsored by Dota. But I have not been able to find a solution to create and schedule matches inside game. If you’re a platform like Challengermode, you’d likely need to partner with Valve or obtain specific permissions to use certain features.
For tournament platforms, partnerships with Valve can allow deeper integrations with Dota 2.