Thank you for playing and making a video of it! I always love to see how people react to stuff I made :D
You are right, those were Pebble's parents. I planned multiple endings for the game depending on how many shards the player collected in their playthrough but sadly I didn't have enough time to implement them all.
So don't worry, you got the correct (and best) ending.
Maybe I'll get around to creating the other endings as well in the future.
Thank you again!