This is fun kata but 6kyu is too high imo.
It's not an 8kyu, using dictionary is may be hard for 8 but totaly ok for a 7 kyu i think

Here you sort ALL the 50 millions element and after you had to compare the digit (not linear for sur).

But all you have to do is to look element by element and find the first one who is not asc (linear).

Sorry for my english

it doesn't work lool can someone explain why this is if you have time?

Ok so I submitted this solution and it was asking me two rows instead of just 1. I was unable to complete the challenge.

Ranks can't be changed!

5kyu it's to much for me, it's a good 6kyu not 5

everything is correct with logic

Nothing is correct with this logic. You're providing only partial implementation of sort function. It may work in later node versions, but you can't rely on that.

expected '[9,9,9,9,1,2,1,1,3,1,0,0,0,0,0,0,0,0,0,0]' to equal '[9,9,1,2,1,1,3,1,9,9,0,0,0,0,0,0,0,0,0,0]'
            your function returned this                               this was the expected value

Fix your code.

Instructions: Write an algorithm that takes an array and moves ALL OF THE ZEROS to the END, PRESERVING the order of the other ELEMENTS.
Log arr: [ 9, 0, 0, 9, 1, 2, 0, 1, 0, 1, 0, 3, 0, 1, 9, 0, 0, 0, 0, 9 ]

expected '[9,9,9,9,1,2,1,1,3,1,0,0,0,0,0,0,0,0,0,0]' to equal '[9,9,1,2,1,1,3,1,9,9,0,0,0,0,0,0,0,0,0,0]'

Where in the instructions it says that 9 needs to be moved to the beginning, fix it

There are 4 nines in both arrays...

Look on the top of the page: this kata has been solved about 80,000 times. Please don't raise issues lightly.

Yes you can see this on the test cases ;)