Okay, when in doubt... fight plugins with plugins!
I used Peter Van Weston,
www.nonumber.nl
, used his ReReplacer plugin to remove the mootools1.2.5 script ONLY from the VirtueMart component. Easy enough fix until the day that everyone updates their stuff to be compliant with the latest standards and friendly with every other component / module / plugin / framework.
I'm sure that day is just around the corner!