Yeah I don't know if they do it because of government regulations or what but anytime you add in 3rd party it seems to create issues. Maybe Overkill can confirm this.
I'm ok with her coming back to me, if it's a simple fix like this I'll do it because it creates goodness around the office, if it's something more involved or that could find me sued by working as an unlicensed mechanic here like if it were brakes that she needed etc. I wouldn't touch that. I'm fine doing it for myself and immediate family but no one else. Not risking what I have worked hard for.
The reason I could get away with this at my dad's shops is because he "inspects" work after it's done so this is a bit of a grey area and sort of allowed. Not that I would ever do something unsafe or that he wouldn't do himself.