done these b4 same settings and im happy with the pencil pot and crystal but the slate has come out ginger to not just my girls hair lol
didnt like doing the slate as says prewarm and it started to cook the ink while lining it up as you can see between their heads the line
The slate was too warm before you placed the image on it. So less time to preheat.
It looks to me as though you didn't use the ICC on the ones that wrong.
wrong icc or not used at all to me... or maybe some setting has changed? its defiantly to dark and red.
reduce some time in the oven as they could be over cooked.