I'm having a hard time believing that
A few days ago, we learned about Era's Adventures 3D, a new Android game that stars an unlicensed character model of Mario's faithful mount Yoshi. It sounds incredibly ballsy that anyone would pull such a stunt and not anticipate the consequences. As it so happens, the creator is claiming complete ignorance about Yoshi's identity.
In responding to Ars Technica, Era dev Botond Kopacz stated, "Actually this is an indie game developed by one developer, so due to the limitation of effort, I purchased a cute character from TurboSquid, one of the biggest 3D asset stores, without knowing the background story of the character Yoshi, since I'm not a Super Mario fan.... Once the game was released on the Play Store, after spending hundreds of hours in making the game, I started receiving 'kind' mails from Super Mario fans that I stole Yoshi, etc. So I started Googling and I realized that the character is really from the Super Mario series."
Naturally Kopacz is planning to alter the model, but I nonetheless find it highly unlikely that a non-Mario fan who is nonetheless invested in gaming would not at least recognize such an iconic figure from the biggest gaming franchise of all time, even if he couldn't identify Yoshi by name. Has he never seen a T-shirt, webcomic, video, or news article that featured the green dino? You'd have to work extremely hard to keep yourself completely in the dark.