It could be that Tim Hennis is the culprit after all. However, the Hennis case is one of the most bothersome because it was an extremely circumstantial case and left unanswered questions that still haven't been answered despite the recent conviction. And whether he is guilty or not, that prosecutorial misconduct early in the case was inexcusable (and the fact that the prosecutor resorted to it says something about the strength of his case against Hennis). Ditto the sloppy investigation because the police were under political pressure for a quick resolution.
The original case was a weak one and depended on an eyewitness whose story changed several times, and later another witness seeing someone use the stolen ATM card but whose testimony was discredited at the second trial (yet these same witnesses were used again at the third trial). There was nothing to tie Hennis directly to the murders: nobody actually saw him do it or clean up, no physical evidence, no motive, nothing from the Eastburns' house to tie with the Hennis's (except the dog) and vice-versa, and no confession. And Hennis had been in the house to answer the ad about Dixie, which would give him some layout of the house but would compromise some physical evidence.
And there were unanswered questions that were not followed up and remain unanswered: Mr X letters, the babysitter, possible drug connections, threatening phone calls to Mrs Eastburn, the blue van, the post-altering of the crime scene Mcdonald-style (why go to that trouble when you can just burn the place down to destroy the evidence?), and the sightings from Charlotte Kirby. And there is the Jaye Mintz case that was disturbingly similar: the killer apparently getting on on pretext of answering a classified ad, then tying up the woman, raping her, and then slashing her throat in front of her baby.
The Hopper DNA evidence is still the rub. However, some can argue that the sample may be contaminated as it was not preserved properly at the time. To make matters worse, this case has a history of prosecutorial misconduct. And there is unknown DNA that was not tested.
Innocent or guilty, I bet Hennis wishes he'd never answered that ad about the dog. Hmm, if he hadn't, could the police have gone after Raupach (the true "walker") instead and used Cone as the star witness against him? Raupach's habit of walking in the area during those early hours could easily have been used against him, along with his knife collection and his D&D. I don't think they would have really found anything concrete against him, but Hennis's first conviction is proof you don't need hard evidence to get a conviction.