If not for this singular woman, who's now gone to be with her beloved son, these two monsters would still be for loose and fancy free, living their lives as if nothing had happened.
But Ms. Cheryl Williams knew in her heart there was something amiss- and at great personal cost (Denise withheld any and all visitation to her only grandchild for the entirety of her childhood) and despite all she had to lose, Ms Cheryl risked it all, relying on the few good people left, and a journalist, an ATF agent, and Brian's wife Cathy to realize she was right. It took far too long, and it's sad no one was going to face charges for Mike's murder, but ultimately, the two monsters that took him from his child rather than filing for divorce are behind bars and it's all you can ask for.
I'm unsure of the reviews blaming Cathy for anything or that she 'knew' something, but that woman went above and beyond anything anyone could have expected. Now if we're talking about Blythe? Well there's someone deserving of scorn and ridicule, and blind allegiance to someone who would throw her under a bus if it meant her own freedoms, but it's all moot.
There's a lot of details this series failed to make mention of- like the great lengths and cost to Ms Cheryl- getting expert opinions from anthropologists, reptile experts, topography experts, etc., and they all called her a crackpot. That's the secondary victim here, and I sincerely hope she felt at least somewhat vindicated.