Why is the ELO calculation method of this game not set up properly?

[KuronoJoucho]

I noticed that I only got 1ELO after winning in 3-player high difficulty mode and other settings, which may be wrong according to the ELO score of other cooperative game settings.
For example, Sky Team or other cooperative games, 3 people will get higher elo than 2 people, and hard difficulty will get higher elo than normal difficulty, which is undoubtedly good, so I would like to ask if anyone can improve the elo calculation method of this game?
Thanks for reading.

[Jellby]

Some cooperative games just give 1 elo per victory. Some give 1 elo per game (victory or not). Some give 10 elo per victory, regardless of the settings, etc.