There is no chance he left remains on the property. If he did kill her, he likely used his science background to dispose of her corpse in a way that would leave no trace behind.
I'm not convinced JFG has the appropriate science background to have the skills to do something like that. Forensics have come a very, very, long way. You would be surprised the amount of information that a competent forensic scientist could glean from the smallest amount of remains. Even then, if something like DNA can't be found, there are still trace elements that exist that could indicate the presence of some form of remains being there at some point. The only people I would think so capable of disposing of a body completely are ones that have the manpower and resources to ensure it doesn't get found like large criminal organizations. JFG is but one man, even he can't remove every single trace.
I don't know if this is something that they would actually do, but it would be funny if the RCMP bought his old property off him to more thoroughly comb for clues. If something did happen at that house, then he's a retard for leaving. He just gave up any control he has over how much they can investigate that area. Either that's why he ran because he knows he can't postpone being caught forever, or he's so overconfident that he covered his tracks that he thinks that it's okay. Even if the body isn't on the property, I think it may have been where the murder happened.
Also as much as I think the tard rage theory would be funny, I think it was premeditated based on a couple reasons:
One, this is obviously something that has been a long time coming, Mama JF says on camera that he tried to kill her.
Two, he created a false trail. The shit with the cameras seeing Mama JF after the last time he "allegedly" saw her and his claims about her phone could all easily be lies. He could have dropped her off and picked her up somewhere else and made sure nobody else saw Mama JF with him. Phone GPS info can be easily spoofed, or just chuck the phone in a public trashcan. It will keep pinging towers from the garbage truck when the trash service comes to collect, as long as its moving and has battery life it will cause the phone leave a trace as if someone is carrying it around.
Three, he redid the inside of his house shortly after she went missing. If that isn't a red flag I don't know what is. It would be even more damning if he bought the supplies after the murder would have happened because it shows maybe it didn't go as smoothly as he would have hoped. I would have thought JFG to be meticulous enough to set up some kind of Dexter kill room. It makes you wonder what happened to all the stuff he pulled out of his house and how he disposed of it. This and the fact that he chose to leave maybe shows he had some kind of guilt or paranoia associated with the location he did the crime.
Lastly, four, you can tell in his demeanor that he is unbothered and almost smug regarding the disappearance of his wife and mother of his children. That just isn't normal. Any self respecting true crime JCS enjoyer would know that most people are pretty distraught when their spouse goes missing. When they get accused of being responsible when they truly aren't, they become rightfully indignant. JFG takes great pleasure when people ask him about Mama JF and you can tell. He delivers his spiel with the same arrogance of the winner of a competition describing their strategy. Whether that's him trying to convince himself he got away with it, or if he truly believes so is anyone's guess.
I have zero criminal justice background, but that's just what I see from everything. But if I can see this shit with zero experience, I would be surprised if someone isn't building some sort of case on him. Unfortunately I think government organizations like that have to move slowly and deliberately on purpose as to not show their hand before they can take action. It's one of those things where they have to be 100% sure they can get him because they only get one shot, and the consequences of making a mistake could be dire for them. Maybe they'll just do an Al Capone and catch him on unrelated charges and use that to corner him on the other shit.
