When Gretzky played for the Rangers - they wore Starter jerseys - that would have the double logo on the back hem. No picture of the hem raises an instant red flag. Also, Gretzky wore size 56 jerseys, and there would be velcro strips on the right side to keep the jersey tucked in.
No pictures of any telltale signs of a Gretzky gamer is more than enough to run away. Plus at that point, you can guarantee that ANY Gretzky gamer - especially in the last couple of years of his career would have some kind of an LOA attached, just for security purposes alone.