How observant. Yes, you're correct: Merlin is missing! And what's more, we have confirmation that he's not coming back, although no one can tell us what happened to him.
A call to the Excalibur led to some sleuthing on their part, as no one had informed marketing that the wizard was gone and nobody apart from you had noticed! Inquiries were placed with the maintenance department; they revealed that they'd taken him down in mid-March, although no explanation was forthcoming, nor were details of his fate. All that they could reveal was that his removal is permanent. Marketing speculated that it's probably a reflection of the property's deliberate move away from being a family-oriented destination to a more adult one, with shows like Thunder from Down Under and the new Octane ultralounge. (Only a decade or so behind the rest of the city, then.)
Although Merlin may have performed a wizardly vanishing act, apparently there are no plans that anyone knows of to ditch the jousting tournaments. Then again, no one knew that Merlin was for the scrap heap until he disappeared ...
P.S. No, this is not an April Fool's joke!