Head, miss, and ? (Divinity: Original Sin)

Collected all 16 inert/bloody stones. Inert grey somehow more work. But only red and grey together should be 16. Come to the head behind the boulder in the Temple, and she says I don't deserve to pass. What do I do now ? I thought that the main condition is 16 stones. But there is one caveat. Judging by the info in the Internet, I have opened all the rooms at the End of Time and the pulse-historian is missing