The labyrinth tiles in Capella Sansevero where built between the mid 1760s to c. 1771 (according to http://www.museosansevero.it/floor/?lang=en). They look like this:
I saw the same pattern in Villa dei Misteri in Pompeii. Here's a picture:
The patterns are almost the same, and it seems unlikely to be a coincidence, specially when both buildings are quite close.
As far as I can find, the Villa was not excavated after 1909, so it would not have been known when the Capella was built. From what I've read, several buildings in Pompeii were excavated around this time, but the frescoes of these places were removed and the buildings buried again. Since the fresco in Villa is in great condition and relatively far away from the rest of Pompeii, it seems unlikely that it was unearthed and buried.
Maybe this is a somewhat common pattern and could have been found somewhere else? Or is it just a coincidence?