I was chasing similar info around 10ish years ago. I actually spoke to someone through the inquiries line, (not sure if it was general or a specific section).
Knowing they would not give the info, I asked anyway...... well got to try! The girl laughed and suggested I do what I stated previously to do.
As it turned out I had the matter resolved before writing the letter to the (RTA) RMS.
I would forego the local and make enquiries through a section listed in the yellow pages or their website.
The woman gave you incorrect information just to get rid of you. No registration authority will give out details of vehicle owners or pass on a letter for you as it violates all privacy policies and laws
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