Those are all good questions. Since the murders, most have been answered. In the following interview with BJM, she discusses a lot of what happened that morning.
http://www.cincinnati.com/story/news/2016/05/11/pike-county-not-leaving-those-babies-there/84194756/
She went to FR's trailer next door, to tell Frankie his father was dead, as most of us would have done. No one told her not to go there. Frankie's trailer was locked. She pounded on the door asking for Frankie to open it. She heard the toddler Brently inside, he opened the door. She went in, saw the carnage there and took the infant, Ruger, and Brently outside. As she was quoted saying: "I was not leaving those babies there." Most of us would have done the same.
In the interview she also said there was another couple with her that morning. In interviews, she said she thinks one of the couple may have followed her into one of the trailers. No doubt LE has asked her to not speak publicly about the case, so IIRC, she hasn't said much about the other couple. Internet speculation has been that they came by to water plants in CRSr's grow op. It's probably safe to assume she knew about it, but perhaps she didn't.
Yes, there's a lot we don't know. Yes, it's reasonable for LE to focus efforts on the people who discovered the bodies. It's also reasonable for LE to focus on the last people to see the victims alive. Until very recently, with the raid on the Wagner family farms, there was no indication LE was doing that. The murders were over a year ago and it's reasonable to ask why it took LE that long to search the properties of one of the last people to see the victims, who was having a disagreement with them.
It's also reasonable to ask why an outside reward for information was initially discouraged and later, information about the CrimeStoppers reward was not publicized until someone in the news media asked about it. In any investigation like this, it's expected for LE to distribute posters and information about the reward to generate tips, but that wasn't done for many months. The only poster created and distributed was done a few months ago by surviving family members.
The case has been locked down. Secrecy and sparse communication with the public and news media have become routine.
As for political motivations and conspiracies, we don't know. Similar things have happened before in the history of US crime. Neither DeWine nor Gov. Kasich are likely comfortable having to deal with this horrible crime, but it comes with the job description. Two major daily newspapers have concerns about the way the case has been handled and have filed suit to view the unredacted final autopsies. Neither of these newspapers has a history of muckraking, both have a long history of treating Ohio government leaders extremely favorably. The fact that they have concerns is significant. Cincinnati Enquirer and Columbus Dispatch rarely step out of line on coverage of state politicians. In the past, many have considered them the "dogs that don't bark". The fact that they're barking now, all the way to the Ohio Supreme Court, says a great deal.