After the Evelynn blowjob scene, the guide says to go back to her shop the next morning. It then skips to Head to Red Barrier, but Evelynn is not next to the door or with the player in any of the pictures after it, implying the player should explore on their own. However, when trying to enter the temple alone, the game says "I shouldn't go in there without Evelynn."
So then I try going in there with Evelynn, but when I walk through the inner doors to the temple, I don't get transported to a puzzle, and can't interact with anything in the inner chamber.
Edit: So going to the temple with her, leaving, and then resting for a few nights seems to trigger the cutscene. However, when I purposefully left the temple and went back to the city, the ocean sounds followed me and won't stop playing in the background. They did stop once the cutscene was triggered and I went back through the door and into the temple, but having the ocean follow you through the door is probably not intended...