And so, I found on a foreign site that it is possible to replace the save on steam, first go to the folder where our save C: \ Users \<> \ Documents \ My Games \ Rocket League \ TAGame \ SaveData \ DBE_Production \, change the name of the downloaded file to steam id, the easiest way to find it out is in the folder where you save, just copy without the lower space and subsequent numbers.
Rocket League: Save Game (level 22 or 75, 100% Steam open) Free Download
Then we throw the save with the changed name into the folder and delete the old ones. Next, go to steam-settings-cloud and remove two checkmarks. Then we go into the game and voila, you have level 75 or 22 (which file with the level you will throw) and in addition everything is open, regardless of the level that you prefer. I laid out another 22 level so that it would not be thrown to serious players and so that you would not be called a cheater, since this level is difficult to earn.