After Annan left the nightmare, he gradually regained the sense of his own physical existence, as well as the "Siren Object (2/3)" he was constantly holding in his hand.
Annan could clearly feel that he was maintaining a standing posture, continually rising upward.
Without opening his eyes, Annan's perception was like invisible tentacles, crossing the barriers of the Magma Forbidden Tower and sensing that there were quite a few people above waiting for something.
Having regained the reversed Heart of Winter, Annan's thinking once again became rational. He immediately realized that those people above must be the "reinforcements" who had entered the nightmare earlier to rescue Annan.
It must have been the Tower Master who told them that Annan had already awakened and was about to come up... That's why they were waiting for him at the exit of the "elevator." Or maybe they knew Annan was about to leave when he rescued Isaac and Ofelia.
