I don't know if it's meant to work this way or not, but I explored some areas of Whitechapel before visiting Nurse Crane and found Cristina Popa's lost scarf. However, upon reaching her, I was immediately informed that I'd locked a hint for both her and Clayton Darby. Which I sort of understand from a coding point of view, you don't want to trigger the quest after you turn it in, but it's odd since I can end up learning basically everything through the remaining hints from the two of them. I know this isn't exactly an open world and I understand that there are consequences. I don't even plan to embrace either of them at this point. But it still feels like I'm being punished for exploring and not going directly to where I'm supposed to be.
@starliwalker I had the same exact issue. I had a perfect run so far with no hints locked, all were successful, until this moment. The mission allows you to turn the scarf in to either Cristina or Clayton, it seems we both turned it in to Cristina and got 2 hints permanently locked. The funny thing is, I’m almost positive I spoke with Clayton after I got the scarf, before talking to Cristina, and there was NO option to turn it in to him...so a lose-lose situation. I’ve put about 15-20 hours in and this just ruined my hint streak...I don’t know whether to quit or start over from the beginning. Extremely frustrated.
I have exactly the same issue. I picked up the scarf and the quest log sais: "Choose what to do with the lost scarf" but my only option is to return it to Cristina Popa. I'm unable to return the scarf to Clayton Darby. I have listened to all dialog options for both of them and did the eavesdrop before picking up the scarf. This definitely has to be a bug.
Even with the patch released today, I still have the same issue.