Never mind, did that and got the vertical one after three tries. Figured the trick was probably that I managed to do it a tiny bit faster than before (that's kinda BS cause it definitely didn't take me more than 5 seconds per ring before as the robot says), so I tried a few more times on my real file and got it. Then went for the other course, restarted it until all the rings were there, and even though I didn't seem that fast this time, it worked for some reason.
In conclusion: that game's out-of-whack.
Then I found the remaining cards in Brokken Volcano and game's finally over. Unfortunate there wasn't anything for all the effort of collecting those cards though.