Nothing wrong with those clones at the top of page,At that age don't worry about how they look if there green and has long has they stay green just do not rush em ,Wait till they get a nice root mass and then put in your medium.I have never been a fan of that type of cloning tbh .I prefer rock wool propagator and misting for a week ,then after that make them work for water ,they need a bit of warmth ,but again i'm not a fan of heat mats .They should get enough warmth from a light ,i use a small plug in heater works great 10/10 with every one i've done .Just be patient they will be fine