Thank you for your reply. Yep, all workflow is RGB. Color settings between Photoshop and InDesign are synchronized. Photoshop layer blend mode is set to multiply, I thought I had tried setting it to normal, to check if that was the issue, but the problem persisted. I'll try again today. It would not be surprised if that had something to do with it though.
There is an image showing the problem in my original post, would you like to see a sample of something else?