I recently found out that the burial marker that once laid there was kept by a studio staffer once the time capsule itself was removed. The marker is solid metal with a diameter of 42 inches that weighs almost 45 pounds.
Turns out as they closed Nickelodeon Studios, they were opening Nickelodeon Suites Resort, also in Orlando, Florida. The time capsule was quietly transferred to the hotel and reburied in front of their lobby with an updated marker. The fandom soon found out and it became a tourist attraction.
I haven't been able to find footage or pictures that shows the square in full detail, so unless someone who works or visits the studio takes a picture of it and posts it online, there's really no way to tell.
After going missing for 16 years, the original time capsule burial marker that sat in front of Studio 18 in Universal Studios Florida from 1992 to 2006 went into auction at Heritage Auction. It sold for $19,200. The back of the cover has a list of all the object that were put into the capsule.