could there be a 100% board?

No for 2 reasons:
The game doesn’t track your % completed for your save file unlike a couple other GBA movie tie-ins that I know of.
The idea of 100% collecting all these items just to do the minigame at the end of every level. It just doesn’t really have much appeal speedrun wise.

Hopefully that makes sense that a “100%” run just isn’t a real prospect.

As a whopping 25% of the speedrun community for this game, I agree. I'm not interested in collecting 10 bubbles or 1 star and memorizing (if they're consistent) or grinding (if they're random) 12 puzzles that add no extra gameplay.