It sounds like sunburn could be a possibility, or a surface pathogen exacerbated by lack of airflow. The wildly changing conditions can be a hard adjustment for plants. It's not uncommon for cuttings to discard all of their existing leaves while taking root. When that happens, snipping a little nip of the tip can let you see if it's still alive inside or not. If so, new foliage should appear soon. It's hard to cover the possible realm of guesses w/o seeing a pic, and may or may not help you figure out what happened.
IME with bring PS inside for winter for several yrs in OH & for about 5 yrs, it's a difficult plant to keep looking good over winter, but keeping it alive so it can go back out & be gorgeous again in the spring has always worked for me. Last minute cuttings in the fall after it's gotten chilly at night have been much less reliable than ones taken earlier while plants were still in prime condition. For that reason, I wouldn't rely only on fresh fall cuttings to sustain this plant over winter.
It's hard for me to keep up with the story of these plants with so many different posts about them. My memory just isn't that good. Wishing you every good vibe & the best luck though! The only way to succeed is to try.
