It is NOT the same.
The tonga at RFC is just regular old French toast with sliced bananas, strawberries and nuts sprinkled on top, good, but not exceptional. Kona's Tonga is stuffed with a banana filling and then rolled in cinnamon sugar - quite unique, but a bit sweet if that's all you're going to eat. I'd suggest splitting Kona's tonga with someone else in your group who is getting something more substantial, like an omelet or Eggs Benedict.