Rare Game Mystery!

If you like anime, you'd love to have this game: SPEED RACER for Genesis!

I kept seeing a game listed for the Genesis in the 90s called "Speed Racer". I know a version came out for the SNES. I thought it was just a mix up because I had never seen the game.

Years later, as I started collecting, I continued to see the game listed in ads and on dealer lists, BUT never on collector lists. So did it exist or not? Maybe vaporware. Maybe a prototype.

Now, I find this ad in Sega Visions Apr 94. It shows game graphics very different from the SNES version. That could mean a proto exists. I have yet to find the ROM. The graphics look clearly GENESIS.

What do you think? Exists? Prototype? Vaporware? Anyone have a clue about this game?