My opinion, and I believe everybody has the right to their own opinion. Consider all that this family has been through in the past week. I imagine both of the parent's are being treated medically for the amount of stress they are under. That could very much explain the differences in the most recent interviews vs the earlier ones.
As for the dumpster fire, I just don't see the big deal. They live in a pretty heavily populated area, dumpster/trash can fires are probably pretty common. Were I now live, people regularly burn their lawn clippings, downed branches and leaves. When I lived NJ, I wouldn't necessarily know if there was a dumpster fire or brush fire that wasn't big enough to make the news headlines.
I agree, I don't see why it is so important that she didn't mention the dumpster fire to Jeremy. Unless I set the damn thing it wouldn't register on my radar. Of course she can't lie if she heard about it then that would cast even more suspicion on her.
Honestly I'm surprised they are still talking to the media...everything they do and say is being scrutinized negatively. I bet if they were on the floor sobbing uncontrollable the opinion would be that it was too much and therefore they were faking it.