Ironically, the solution to electronics that get wet is to put them in a bag with rice
That is not really practical in this case. I would call the manufacturer and ask what they recommend.
Mebby heat the oven to 200*f, once at 200 turn off and place cooker inside with towels around it. Or letting it sit in the sun with a towel around it if you live in a sunny area.
Heat isn't the only thing that dries... I would rather wick away the moisture, or otherwise soak it up, than subject the cooker to heat which could cause further damage.
I dropped my cell phone in water, immediately took out the battery and put it in a bag of rice for a couple of days . Did the trick, works just fine.
Rice is a good idea. I don't know how effective it is with moisture that is internal to the rice cooker. I'd go with a combination of warm, dry heat and rice.