Wet Key FOB, car goes chirp chirp

Better not to get drywall mud on the key FOB (what does FOB stand for?) but even better not to wash it off. I've had it not start, car goes into panic mode, and after finally getting it home it is still causing the car to chirp.

How does one get the FOB apart to remove the battery? Thanks.

Found a video online. Basically key open to the left with vw emblem towards you, place right thumb in groove and pull cover towards you. It pops right off.

Now I'll probably have to wait a week for this thing to dry out.