I think both of those are possibilities.
The plastisol though clear still could have been too hot because you're suspicion is correct, I dont have a thermometer. And it seems I need one.
Plus, the chartreuse colorant was translucent and the effect did look lime green afterwards so I suppose that could be it too. If so, I'm bummed. I was trying to reproduce a lure color that I used to be able to purchase which is no longer available. It was a light chartreuse color with green & black glitter. This was my ho to in every body of water I fished when I couldn't get a bite so accomplishing this is important to me.
Of course, using green glitter in the chartreuse worked for the manufacturer. I wondering if they used less glitter to avoid the effect you mentioned (and possibly a lower temp too?).