So, during another play got to see the scene where the tadpole calls to you, and yes, it is Raphael standing next to you, managed to smash the print button fast enough. That being said it came right after meeting him, so I think it's just a glitch showing the NPC that is probably just invisible in your camp for game purposes, not relating him to the dreams themselves. Haven't tested, but I believe sleeping in the "uppermost" cot (the one in the direction of Astarion's later on) you can also get a view of it after the encounter. That confirms the claim in OP's list, but might not be adding anything in the end.