Well, er... we wouldn't find any info of a person successfully hiding their body after committing suicide, would we? I'm sorry, but this thought caused me to chuckle. Not a laughing matter at all, but once in a blue moon it's ok to smile, I guess.
I began googling it after reading your post, before it dawned on me that there could not be any meaningful statistical data available for people who've probably committed suicide without ever being found. Those folks, however few or many there are, remain missing
Same for those who have successfully walked away and now live elsewhere, evading detection. That seems harder to do in this day and age, but if a walk-away committed no crime and is an adult, they do have that right.