The Dink Network

I got one question - may include spoilers - I got a piece of all 4 crystals on me, I am already in the riddles area. I think I found the place in which I should be able to put those crystals - the 4 stumps that were guarded by 4 slurpers. The problem is that Dink is not doing anything when I space near the stumps, using ctrl while having a crystal loaded also does nothing.
On one save I cleared the fire forest from all fires and at that time the guy in the house in the right lower part of the forest told me more about a treasure, but since the shaman was not believing that I put out all the fires anyway I resigned from that save.
Can I get that treasure without having that previous conversation?