I think he is one of Russell's closest friends. Possibly a confidant of Russell's. And president of their ham radio club.
I do think it is interesting that they always comment that he was the last known person to talk to Russell.
But perhaps he is one of the only ones who really wants this mystery solved, and is willing to speak with the media. I have yet to see any of the other family members - other than Russell's wife - speak with the media, or beg people to help. Keep the profile up. Family have just issued a couple of written statements, as far as I have seen.
Even Russell's wife just sort of seemed to say 'oh well, he's dead by now'. And started clearing out his belongings.
“The complete radio group are at a loss because he’s been friends with all of us and when we catch up of a night time and all that sort of thing, there’s always a bit of camaraderie and stirring and all that that goes on and Russell’s dry sense of humor was always part of that,” Mr Ashlin said.
“I think they’ve been murdered”