Mimo777’s Party Clue

Ok, this morning I figured out Mimo777’s party clue. Im not sure if Chuchskate got the clue, but I did. I cant give the clue away but Im willing to give a hint! Alright, it has to do with the Polybius Square Code. Here are the #’s:

31-32-42-43-53-53-13

And the Polybius Square Code:

Now dont think im gonna tell you the answer because im not. Im sorry. But Mimo777 is literally the man. And im gonna follow his orders. mkay? mkay. Comment fa show

Hezakiah789