Dillion Harper: One Night Only

I should check if "One Night Only" is an official event from J.K. Rowling or a fan creation. Let me think. There was an event called "One Night Only" in the UK in 2000 where a lot of charity fundraising was done, including events linked to Harry Potter, like the "Harry Potter: One Night Only" concert. That concert featured various artists performing songs related to the "Harry Potter" franchise. But Dillion Harper isn't a character in the movies or books. Wait, maybe it's a mix-up with another character? Or perhaps there's a fan fiction or a fan event named after Dillion Harper?