IMHO, I'm not convinced DG's green truck was the only method of transportation used.
I still think it's entirely possible that DG parked his truck in the back lane behind their house, gained entry either by slipping in an unlocked door or by being let in, and left with the 3 victims in AL's truck. He disposes of the 3 victims in some manner or places them somewhere to deal with later, brings AL's truck back, cleans up quickly outside the property, wipes down surfaces he remembers touching on the inside and leaves out the back way of the Parkhill home and drives away in his truck.
It was mentioned that SpyHill landfill is where garbage would go from his parent's property although I suspect they haven't found much there. I would suggest that he is fairly thorough and methodical in his approach.
Problem is, he had a few days before LE was on to him. He had a number of chemicals at his disposal and he more than likely planned and plotted this out. Yes, he got caught out by (probably a plethora of) CCTV cameras, they may prove to be his undoing. Sucks to be a loner and not engaged as much in the real world.
Also IMHO, I think LE HAVE found trace evidence of chemicals in his truck that match chemicals found at the acreage. Still not 100% convinced though he took the 3 victims to the acreage, I still feel he didn't go far. He was a child, early teen in the Bankview/South Calgary neighbourhood (16th Street/26th Avenue), back in the day when children ran free compared to now. I'd be looking in South Calgary Park (which is not far from the Parkhill home), again IMHO.
