I am having a similar problem, with a lot less points148477 but I have played 255 rounds.
Moved up to Master by playing several matchplay games against master and tour master and beating enough of them to tier up. Tried the same approach now I am master and it worked to a point. Reached average of 66; beat 4 tour masters and th average has not gone down. I have blocked 5 tour masters and 3 legends that quit when they were about to lose.
Its a no brainer to say they would not have quit if they were in front.
A new trick by some of them is to go through the process of getting themselves disqualified.
Hope this helped.
Oyanglon