There is literature supporting a significant correlation between left handedness and higher intelligence. One explanation is that lefty's have to live in a right-handed world and this contributes to a better developed (e.g., thicker) corpus callosum promoting mental speed and use of more of the brain (i.e., both hemispheres). Right handed individuals might take it for granted that desks, scissors, etc. are specifically designed for the convenience of right handed people. Because left handed people are to a certain degree likely to use both hands (e.g., car design forces left handed people to use their right hand to shift gears, etc.), a positive relationship between intelligence and ambidexterity seems plausible. Ambidexterity is more likely to be associated with a better developed corpus callosum than being decidedly right hand dominant or left hand dominant.
Good to know about your mindful question! Oh, yes, while the science says ambidexterity is more related to motor functions. Whereas, intelligence is a very complex biological phenomenon which is still a mystery till today's date.
Intelligence is the master controlling switch which leads to ambidexterity.