Someone Stung Waldo.
He seems like the kind of guy who, if he hadn’t been dared to dress up as Waldo for Halloween, probably wouldn’t have heard of the Where’s Waldo book or TV show. He seems like the kind of guy who wouldn’t have heard of the Where’s Waldo book or TV show if he hadn’t been dared to dress up It would appear that he has gotten his names confused.
When he walked out, he looked more like a were-Waldo than like Waldo. This seems likely to happen. This is the most likely explanation for what’s going on. We’re not really interested or motivated to keep an eye out for Waldo because he didn’t show up this way in the book.