CHURCHILL, Australia — The only person accused of lighting one of Australia’s deadly wildfires was a lonely Web surfer who liked dogs, always said “G’day” to neighbors and was trying to find love online. Brendan Sokaluk, a 39-year-old who reportedly once served as a volunteer fighter, was named as the suspect police arrested last week, as the death toll from the wildfires edged up to 189 on Monday. Authorities were forced to keep Sokaluk at a secret location to protect him from potential reprisal attacks after a magistrate lifted a ban on publishing his name.