Hello WhyaDuck,
Firstly, I'm sorry for the loss of your aunt, and secondly, I congratulate you on not letting sleeping dogs lie. This is what it takes! You're someone who can make a difference by getting involved. You can always go down to the police station yourself, and talk to someone. It would be harder for them to dodge questions in a face to face meeting. I think it's important so you, yourself, are able eliminate fact from fiction. From the sincerity of your posts, it's obvious you have questions that only LE can answer.I'd read some of this thread prior to today, but today went through it all. This news about the cell phone is BIG! The question of course it who put the phone there. The phone should be tested for both prints and touch dna. Do you know who found the phone?
If the person who put it there was the same as the person whose house burned then he's really pretty stupid to have just tossed it over the property line at his current residence. The other option is that some other person planted the phone there to cast suspicion on the current resident who'd moved away after the fire. Again, that too would be pretty stupid, but not every criminal can be an Einstein. The fact that this phone turned up in a location where it shouldn't have been at all has homicide written all over it.
It could be that LE has an ongoing investigation, but put word out otherwise so as to get the perp to relax. IIRC, you once said, LE had closed their case on your aunt. If that's true, they now need to reopen it, and if they don't then someone needs to contact the DA's office pronto.
What ages are the sons of your aunt, and what do they do to earn a living, same for the ex-husband too.
You could call the fire department to find out if there was an arson investigation on the house that burned.
If you can, find out if your aunt was bombarded in life by one or both of her sons asking her for money. Greed is probably the numero uno reason someone in a family kills another member of the family. After that, its probably alcohol and anger combined.
But by all means, take your time, and don't overload yourself emotionally. Play nice with LE, and if they don't wanna answer your questions, go all teary eyed on them, and tell them how fond of your aunt you were. It'll be obvious to them you aren't play acting. They may open up more after that.