I actually think MDMC could work on the outskirts of Rivertown. Not necessarily include it as part of the land but maybe unofficially theme it in…
Repaint the tracks brown/black/grey, paint up the bikes and call it Dirt Bike Derby, or Rivertown Racers etc.
Throw a bit of rusted corrugated iron around the place, some drum barrels, remove the green/yellow roof over the launch and put a timber shak style roof over instead… it wouldn’t take too much to blend it in. If they leave it as is, it’s going to stick out like a sore thumb, and take away from Rivertown.