Thank you for bringing this to our attention, I will log this as a bug to have it looked into by our engineering team.
I have a workaround for the time being, but there is a slight problem. The workaround is to add the following code just before the closing </body> tag:
Spry.Widget.TabbedPanels.prototype.onTabClick = function(e, tab)
the problem is that if you trigger an error on the first tab, then trigger an error on the second tab, then click back and forth between the tabs, the tooltip will briefly move to the top left of the screen, then reposition itself.
We will look into a better way to fix the issue in a future update to the validation tooltips extension.