So, the only damning piece of evidence you described can easily be explained by Avery leaning against the hood of her car when he went out to meet her for the pictures.
Regarding the EDTA, I agree that the initial response by the defense was not effective. However, the second expert reasonably and effectively explained how the FBI's testing method could have been flawed. As a juror, I would not have placed any weight on the FBI testing.
The second expert only explained the limits of scientific investigation. We can't ever prove with 100% there is no EDTA in the blood in the car. We can only say what we tested didn't show EDTA. If no EDTA is detected, it's the logical result between two things: Either there was no EDTA present or the test didn't detect it. I don't know what the certainty level is behind the test but for it to be admissible in the court means it's results should be accepted.
I actually listed a few pieces of damning evidence and I also believe everything together is comprehensively damning. Some pieces are coincidental but too many coincidences make the probability continue to rise. When you hear hoofbeats in Indiana, you look for a deer, not a zebra.
I find it funny that when people say that it is possible that they cleaned the entire crime scene of DNA and any blood in the garage/bedroom that they just miraculously forgot to clean the car of their DNA just leaving the blood there in clear site.
Also if they were smart enough to hide the car in their own auto salvage dump right behind their house they wouldn't be smart enough to clean an entire crime scene.
This is a fair point and one I wrestled with during the show (and still do). I was team innocent almost 50% of the show. I kept going back and forth but everything together was too much. I do believe what you bring up is a valid question: how did they manage to clean the crime scene so well but forget to clean the car? And how did they forget to use their car crusher? And why didn't they use the incinerator for her body?
These are valid questions that most of us would've done if we were murderers but I imagine the majority of our posters aren't 70 IQ'ers. (let's not speculate on which posters may meet that criteria, I'm sure some may assume I do given my stance in this thread

)
I'll answer these in detail when I can get to a cpu, but you're missing some major points of why the info in that article is misleading (it's the same article posted on a bunch of sites). But here is some high level;
- They claim that this info was all missing from the documentary, when the cat and gun are clearly both mentioned. Not to mention, they are misquoting as the cat was not covered in oil and it happened decades before the crime. The gun also had no sprayback on it and the dna expert testified that it would have had to had it if it was the weapon (after all , it was a squirrel gun). Not to mention, this was also found by Leck during the 8 day access to his property.
- You do realize that his family owned and ran a salvage yard, right? In the show (again, they claim it was missing, it wasn't) they clearly mention that they had auto trader come often because... You guessed it... They own a salvage yard. Seems like a good reason for buying a common tool like chains as well.
- Keep in mind, Brendan's entire admission was first TOLD to him and he simply agreed or gave one word answers.
- You claim to believe that the rape happened in the garage. Where's the DNA evidence? No sweat or semen was found. Do you also believe she was killed there? It would be pretty hard to cover up the dna evidence of a rape, double stabbing and gun shot inside of a garage.
I could go on and on. But it's all despite the fact that Avery and Brendan clearly did not receive fair trials. Which everyone is entitled to.
To the bolded: important note about it happening decades before the crime but still somewhat relevant. Isn't it known in psychology circles that animal cruelty is a key precursor to human cruelty/violence? It's not a guaranteed progression but it should still be kept in mind no matter how long ago it occurred.
The DNA expert testified she would've expected the gun to have DNA on it if it were used for a close quarters shooting. There are a number of ways to clean the gun after a homicide, especially if you have a few days to do it. He could've also shot her from a few yards away to avoid contaminating the weapon.
We're in the realm of speculation so I don't want to go too far with it.
I thought Stephen received more than a fair trial. If that evidence had been discovered in our homes, the trial wouldn't have lasted 3 days. That is damning evidence and it was only his defense team that bought him so much time.
Brendan's trial is a toss-up. His admission was obviously the biggest piece of evidence, coupled with his cousin's statement that was ultimately withdrawn. The lack of hard evidence is difficult to grapple with but with the body burned (expert testimony claiming it was on-site), it was impossible to test for semen, beneath fingernails, etc.
I'm throwing this out there not as a juror but one of the public, who consumed this post trial.
If Stephen and Brendan didn't do it, who killed her? I'm interested in the theories.