you find an ancient register. Each of the greatest detectives you’ve heard of has written their name on it - and to think the challenge was to find it! 4/4
It’s your turn to inscribe your name in it: https://forms.gle/xE4LyEQhfbzc39H78
It took me so long to find this location to finish the search game, that I was too late to submit an answer.
It would have been nice if the ingame link, would have directed me here instead of the general discussion forum.
Or maybe I missed something… 
The last clue hinted you needed guidance, hence the Tips & guides category.