I agree, when I lived in Chicago, the indicators would 'fog-up' a bit in cold weather, without having been exposed to rain, or water from washing .
I put a flood lamp a few feet away from the instrument cluster for an hour or so, and the moisture disappeared .
Once your riding season is over, and the bike is parked, you could remove the indicators, and put them in your oven, with the light on, I've done this a few times, used a 100 watt lamp, and the temperature would get up to 100-110 F. (38-43C.) in a few hours .