Yeah open up the back (not needed but quicker), stick the watch in a sealed tub with rice/silica gel pack (like when you order stuff) - don't cover watch. Plenty of more detailed guides online, usually about how to fix a mobile phone after dropping in the toilet lol.I'm certain I've caused it - see previous post; I washed then disassembled then reassembled. By rice/silica you mean with the back off?
If you want you can disassemble again and try and get the obvious moisture out first, it will mostly just save some time overall though.