Great question, although I don't have an answer because I do think DdH is one of his victims. I think probably everyone he meets in any area of life is to a certain extent his victim.
With the benefit of hindsight, I just watched Day 4 of the inquest again, the JO evidence. What struck me is how the tone and delivery of her evidence is so similar to DdH's. JO's nightmare is 20+ years behind her, unlike DdH who is still in deep, but she had clearly never felt willing or able to reflect on her dreadful and cruel experiences in 1999. She didn't appear to have ever wondered how RB had so easily and cruelly persuaded her to give him her money, her time, her body, her power of attorney, her house potentially, or why she was led to agree to the absurd Bali/Europe trip with no plans, no money, no tourism itinerary, no nothing. Poor woman came across like a un-deprogrammed cult member, even all these years later. AC asked her a few times whether she had queried anything, or wondered about anything, and no she didn't at the time and appeared to have never done so since. I clocked that AC also slightly lost his cool at least once with a rather sarcastic "Thank you" when she finally answered a question after a lot of wandering.
Interestingly, what she doesn't say sometimes makes her evidence all the more powerful. Her rather blank and naive account of being abandoned in the UK with no money, then her scrambled return to Australia and seeing RB again, with no reflections or conclusions about what was going down, had me on the edge of my seat. During this evidence SL's face several times showed her anger and disbelief at what she was hearing.
It's heartbreaking to see the long-term effects of RB's crimes on JO and the others, and how skilfully he selected his victims for their combination of vulnerability, passivity and wealth. Revenge in the form of prosecution will be cathartic for them, but I hope they get some good therapy and are able to meet with other victims.