When walking towards the famous clouds ladder mentioned in several bug reports, you can instead jump down on the scaffolding on the lower floor. You can from there enter Clouds through a terrace, but once you do, you can never exit again. The quest indicator will point towards Judy, who is now behind a wall and doors you can never reach. You can, however, get within trigger distance of starting the quest, which has you talking to a wall. A workaround for this bug, would be to enable Judy to open the doors when going in to see the Clouds owner.