Yes, Riko-Diko works well as home-grown version of Humpty dumpty.

Riko could be a shortened version of Rikardo so looks like a mok-nomo, has resonance with cock-a-doodle-doo in many languages (Fr cocorico, Ge kikeriki, E kokeriko etc) and was also the name of one of the chickens in Privilegia Vojo. Diko is obviously appropriate.

I believe that Humpty Dumpty was originally just a term for a squat corpulent person.