Kelplots Super Missing Pieces

I don’t know why, but for some reason I’ve never been able to get a plant piece for the kelplots super in Sea world. I’ve spent rubies on the mystery boxes and check the plant store every time its refreshed and never managed to get anything. I also regularly sent out both of the residents that sea world has enabled and I haven’t gotten anything from them either. Also to put things into perspective, kelplots is a plant from sea world and I’ve already progressed to music, and still can’t find a single plant piece for kelplots. Is this a game problem or am I just missing the obvious?