How did Robin Pope really die?

I do & I’m extremely shocked they aren’t going after her husband & finally holding him accountable. It’s clear he strangled her and then dumped her in the water. Anyone that owns a dog that has a bond knows if a dog no matter how scared of water saw their owner being thrown or dumped they will try to go in after them. I mean the only other thing is this guy seems sick enough to throw or push the dog into the water afterwards...especially if the dog was freaking out or in a state of panic. Whimpering and whining and barking for Robin. That dog was the best witness to the crime. I think there was a handful of questions still not released after watching like.
1. Did she have water in her lungs
2. Skull fractures
3. Autopsy results on the dog
4. Any evidence that would prompt them to get close to the water?
5. His complete cellular movement
Her husband needs to finally be held accountable.