I worked at a dive shop through college. We would get flooded Nikonos cameras fairly frequently. The best way to deal with flooding was first, remove the battery. Put the item in distilled water and swish it around to get out the salt water or any water born contaminants. Do this a couple of times, changing the distilled water with fresh. When you are satisfied it is clean and flushed, then start with isopropyl alcohol, preferably 90%. Alcohol will mix with water, so any water in the device will be diluted with alcohol. You need to do this a few times to make any water in the device come close to the 90% that the alcohol is. It is virtually impossible, outside of laboratory grade, to get pure alcohol.
Shake as much water as you can from the device. If you have silica gel, you can put the device in a sealed box with the packets (lots of them).You can re-activate silica gel packets by putting them in the oven at around 100° C for an hour. In a pinch, some pieces of wall board can be activated by heat and the gypsum will also draw water vapor from the air. Give the device a day or two to dry.
WD-40 is not a lubricant, it is just something used to get water our of connectors. It can react with various plastics. It was originally a machine cutting tool cooling/lubricant. It works great if your drilling a hole. It has too many volatiles to be a lubricant for any length of time. I used to drive by the factory in San Diego going to North Island to fly, every day, that smell...