Hello IsseyBukkake,
Germinating seeds in coco is a task for itself, since the coco likes to dry out so quickly it poses a big risk for over/underwatering. Next time, you could try germinating them in rockwool or using the paper-towel method before transplanting into coco. At this point, I would strongly recommend that you make sure to keep the RH at 60%, make sure the coco never dries out completely but still not adding too much water.
Good luck with your project, I wish you all the best! 👽