Can the Mystery Watcher still be found?
Solution 1:
Here is all you need to know about the mystery watcher
Location 1:
Location 2:
Location 3:
Location 4:
Once you have all 4 sigils:
Scanning the fourth symbol that the watcher leaves behind will automatically take you to the Batcomputer screen. Use the right and left sticks to rotate and move the sigil so that its four points match the four locations in which you spotted the watcher. Doing so reveals the watchers final location: the eastern side of the church. Scan the symbol on the wall there to complete this side mission.
Final location:
