The gears of the ADF keep slipping out of place. I have tried using the menu reset function in the Data Registration menu....

Did you buy this new? Do you have a second battery to try? If not, try using a power adapter that plugs into the wall if you have one. IT sounds like you may need to consider that there was damage from the moisture near the waterfall. If that was the case, you could try keeping it in a very dry area. This next idea I am only suggesting because you are in the middle of a trip...You could try drying it out by placing it in rice overnight, to absorb the moisture. Just be sure to keep the lens caps on, and to wrap the camera in a thin towel or t-shirt, before you surround it with rice!!

I am not entirely sure, because I've only worked on a couple of these, but I think the audio jack is just worn out. This seems to be a common problem for this laptop. If nothing is jammed in it, and it just feels loose, your next best option may be to buy a USB to audio jack adapter.