Still lit up bright 8 hours later.... hoping they don't explode!
It's dead or it soon will be if it discharges below the cutoff (2.75V).
If you are lucky and the diaphragm inside the sensor dries before it reaches cut off then there might be a chance of getting it back. Leave it in the rice, You don't have a short cut, if you did the battery would have exploded long before so the only load right now is the LED (10mA) since it remained activated, it will take around 34 hours to completely discharge the battery. If the asic in the sensor works it will protect the battery when reaching the cut off you will notice it when the led starts blinking.
If it doesn't protect then it will be discharged below the cutoff and that will have serious impact on the battery capacity or a fire.
Open the ash cap when you leave it on the rice, it will absorb faster.