It seems like Casey panicked and then disposed of her dead child along with everything else she had in the trunk. She had to have had a "better plan" as to how she was going to get rid of everything. The body was only a few feet from the side of the road... even an idiot could figure out it would be discovered eventually. I'm guessing that poor Caylee was in that trunk when George tried to go in to get the gas cans, and Casey freaked and took off and dumped everything. Or maybe when she ran out of gas on the side of the road she realized that she couldn't leave her car with a rotting corpse in the trunk, and quickly tossed everything in the woods before calling Tony for a ride. For someone that put a lot of planning into their child's murder, the way she disposed of the body was too sloppy to have been part of that plan.
Luckily the syringe was protected inside of that bottle, and hopefully they can test it to see what was inside. Had the syringe been dumped elsewhere, chances are it would never have been discovered, or connected to this case. This might be the only evidence they have to show manner of death.
I certainly agree with you that her disposal of the body and all the stuff with it looks panicked and unplanned. But to me, her behavior in the month after the murder does not look like she had any kind of careful plan for what to do afterward - - and that makes me doubt whether there was any real planning involved at
all. I'm not sure why you think she put "a lot of planning into [her] child's murder" (unless you are basing that on some of the new evidence I have not seen yet) The internet searches for chloroform, "household weapons", "neck breaking" etc. may indicate she was fantasizing about killing someone (maybe Caylee, or just as likely, her parents, considering her conflicts with them and talking about how she was going to get their house and Amy would move in with her ). But I don't think that indicates she had developed a well-thought-out plan for murdering Caylee.
To me, from what I have seen so far, it still seems likely she just snapped-- out of rage or a sudden evil impulse, or else that she was drugging Caylee and caused an accidental OD. (I am not sure if they have any way of knowing if the duct tape was placed before or after death. but it could have been put there after to prevent further leaking of decomp fluid which is probably what had already stained the trunk)
It looked like Casey was winging it, making up lies as she went along when people asked questions about where Caylee was, but mostly in stuck in avoidance mode. It's not like she was constantly in the presence of others or under surveillance, so her (non)action in keeping poor Caylee's body in her trunk for days so that it started decomposing and causing a terrible odor, very pointedly tying her car to the crime....and then finally just dumping the body AND all the other stuff near the road in the woods/ swamp area nearest to her house --That looks like not much planning went on. And one of the most key features of any murder plan is what to do with the body! (not that I speak from personal experience!)
Also, if she'd carefully planned this in advance with the intention of getting away with murder, she would have reported it much sooner (as opposed to not at all) and would not have told a story with a fantasy nanny with a specific name and address easily disproven. She'd have said Caylee was snatched by some unknown stranger, and it would likely have been from a location without security cameras. At the very least, she would have put on an act of being distraught in those weeks.
Just my opinion. Really it is hard to know what went on in the mind of someone so twisted.
