I've used RIT dye (crystals) to dye silkspan (yellow), clear dope (red), clear epoxy (red) and nylon propellers (black). Danny Dirt used RIT dye to dye plenty of APC props black, and they were really black, not blue. I've got to wonder if it was really blue dye that was mislabled or something like that. Or did you use the liquid dye? I've never used that, and I don't believe Daniel did. On the other hand, APC props are nylon/fiberglass, while Thunder Tiger props appear to be vinyl, based on the way they break when they break. Different!
Steve