Missing License Plate Texture

Hi, I have created a license plate for Occam's Razer's map Garfield Heights. I followed the wiki, yet in-game it shows up like this:
View attachment 177379
Did I do something wrong?

File attached. Feel free to rename any files as you wish.

EDIT: Why am I being ignored?
EDIT 2: I am indeed being ignored. Help a brother out, man!