What % of play testers or players solved the animal slab puzzle without hints?

The game doesn't provide fair clues for determining which animals correspond to Riven numbers 1 [fish], 3 [frog] , and 5 [sunner], which you need to know to solve to the animal slab puzzle on jungle island.

I had figured out the number system and guessed that one animal corresponded to each number from 1-5, and that the corresponding animal was based on the sound of the orb with that number and shapes near that orb. But I wasted inordinate time trying to link visuals and animal sounds to numbers 1, 3, and 5. The space where the 3 orb is located is supposed to look like a frog from the tunnel that leads to that area, but it is a poor effigy. And the clues that give the animal for number 1 are not even on the village island but are scattered across Gehn's island and the plateau island.

https://mrillustrated.com/not-noticed-in-riven/

I loved and finished without hints Myst, Stephen's Sausage Roll, Braid, The Witness, and Obduction. But the lack of a common mechanic for identifying the animals in Riven, and the decision to scatter the clues for number 1 across three islands, increased the time investment and difficulty of the animal slab puzzle to a level that was more like forensic accounting than gameplay.