Editing IVs of a Pokemon Box Zigzagoon while keeping it legal?

[13 Black]

I downloaded this site's PKM file of the Pokemon Box Zigzagoon and it passed the Legality Checker... I then tried to edit its IVs so it had IV's of 31 in Attack and Speed, with a legal (or I thought) PID, but it showed this in the "type" field of the Legality Checher when I replugged it in

Type: Never seen this. B-A-D-E (Unrestricted)

How do I make my Zigzagoon so the type shows as "Common GBA Event (Unrestricted)" like the readme says it should be? I really want its IVs in Attack and Speed to be 31, but I want it to pass the Legality Checker! Is there a way?

[Toffeuy]

Maybe that Zigzagoon hasn't been registered in the Legality Checker.

Tell me the IV's you put for it and give me the PID to lemme check.