The Royal Crown Polisher was a character who appeared briefly in The SpongeBob SquarePants Movie where he was being accused of "touching King Neptune's crown," which apparently was a felony worthy of death, or as stated: 20 years in a dungeon. He says that it was his job to touch it, as he was ordered to polish it. Princess Mindy steps in and sets him free before her father could punish him.
Video Game Appearance
The Royal Crown Polisher appeared in The SpongeBob SquarePants Movie video game when he was accused by King Neptune for the same reason. In the video game, the difference was that he did get sent to the dungeon. Later, Mindy the princess, comes to the crown polisher in his cell so that he could polish her dirty mirror to complete her quest to save SpongeBob and Patrick.
He looks similar to Patrick and Gary's Great uncle Carl. It is unlikely, but it is possible this could be him.
He also looks like C.H. Greenblatt, who also was the design for Carl, as well as the name.