Replying to Q1: 

I had said to my clinical psychologist a couple of times over a year or two that I wanted to be assessed for ADHD, but she hadn't followed up on that, and there was slways other stuff to deal with. 

A year or two after I switched to seeing a different psychotherapist, I googled Psychiatrist Assess ADHD Adults Australia and found a psychiatrist who does telehealth assessments. 

She did a general patient history, and asked specific questions about my childhood, and then did a standard assessment questionnaire with so many scaled questions. 

I was worried that my result might be inconclusive, but it wasn't. Based in what I've been aware of, and what people have told me, my answers added up to a very clear diagnosis.