I did this by using a secondary account to set a low record.
Create an account and add it as a friend of primary account.
Set a low score with the secondary.
Turn off PS4(tried for a few days without turning it off and it didn't work that way).
Turn it on(duh).
Beat the score 30 times(you can do it in a single day).
The secondary has to show in the challengers box, otherwise it won't work.