Hello, thanks for your post. I had the same problem of not seeing the romance scene before. I continued to play and I hoped it would appear some time. But a few days ago I reached the point right before the finale and so I realized that I was going to miss it. And your post pointed me to the right direction to figure out the issue and eventually found a solution.
You are absolutely right. The problem is due to
not having the conversation about swimming
. I agree that the dialogue option is quite easy to miss.
