Hi, I planned for this answer to be a comment but I think this is pretty interesting and useful information for whoever is trying to find a solid answer so I might transform it into a comment later if something more accurate comes up. First thing I did was reverse search on google on each image of the tiles and they all dropped the same answer linking the images to something called "DOT language" which quoting wikipedia:
Is a graph description language. DOT graphs are typically files with the filename extension gv or dot.
Now, I know some of these tiles are part of the explorer society quest, they are astral bridges. One between Northport (Nort of carlin) and the other one between Svargrond and Liberty Bay. All four represented by this image which is the only one out of all four that dropped Tibia website and everything related to Tibia when I reverse searched for it. The rest of them just say is DOT language, so MAYBE that's the answer, its just words encoded in DOT language representing something related to the game that google can't really translate. I went to check all of them four and they all look the same as the one I pasted above. I tried looking for the other tiles for clues, I believe Yalahar Cemetery quarter has one of them. Its also curious how they seem to have an opposite pair, just having two of the same "kind" mirrored between them. Also, I just remembered that Cip likes to play with codes like these, carved in tiles, like the ones from the Mysterious Ornate Chest Quest, which are in binary code. I will keep searching and will update this answer if I find anything else.