There's just so many holes. The more holes, the more possible scenarios because of it being 36 years ago, in British Columbia, how long it took to be reported, and how it was/wasn't investigated. Let's dive in.
This is a young couple who like many young parents had several ups and several downs. Wife meets stranger and has her doubts and they try to arrange with brother/mother to take children but it doesn't work out. She was apprehensive about it, but eventually went with it, so, what doesn't stop them from changing their mind and deciding this was a terrible idea and decided to hitchhike back home? Then you have a whole different suspect. The logger wouldn't even think to check in on them because it's 1989 and again he wouldn't think nothing more than they changed their mind. They could have even got lost in the area. Even if they found their remains, it's been over 30 years and unless it shows visible homicide markings, it would be difficult to identify a cause of death potentially. I'm not saying these are the reasons, but it's very difficult to establish a pattern when we to literally anything when there are dozens (infinite) or more possibilities when all we have is point A. Point A is them leaving their home.
(2) Let's jump to modern day British Colombia. 30% (+) of Northeastern British Columbia's forests could be fully burned by the end of this year. I have been tracking the wildfire and extreme wildfire events in Canada the last two years. It's really heartbreaking to see in real time.
I'm always open to suggestions or ideas. If I am incorrect, it's all imo. But, that's how I feel about it at this time. I feel for the families. They deserved a proper investigation then. I am sorry this didn't happen earlier to when they disappeared.