So when I do the investigation (starting from the blood puddle), the first part of the investigation doesn't register, despite dialogue playing. The problem with that is that it makes it impossible to trigger the evidence cutscenes, making it impossible to progress further in the mission.
Hello there @Aelfred2k3!
I'm sorry to hear that you're encountering trouble during "Cold Embers," and that the first part of the investigation isn't registering for you. Would you be able to provide us with a video that shows these interactions during the investigation aren't registered, which is preventing you from progressing with this quest?
I'd recommend uploading the video to a sharing platform, such as YouTube or Google Drive, as this will allow you post a shareable link within this thread we can take a closer look at.
Thanks! 
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