Law enforcement seized my package?

You need to be ready for an arrest warrant. It sounds like they had reason to take the package which can never be a good thing.

Theft of Property 250010000 and Theft of Property 1000060000 means what? Is it a class C felony?

Theft 2500 to 10,000 is a D felony and the second one is a C felony. Yes there is serious jail time involved. I would suggest hiring an attorney...

When a cop fails to announce their presence, what happens when lethal force is used (castle doctrine)?

This is a very complicated answer and can not be answered with this little bit of information. If this has happened to you hire an attorney...

Can someone get a higher charge for being charged with manslaughter twice?

They can use it against him for punishment and if he testifies at trial.

When does the five year countdown on expungement begin?

There is no set countdown day but most likely when you plead. Even though it is technically expungeable it is still at the discretion of TBI.

What is jurisdiction laws in Tn?

I would hire an attorney immediately for your fiancé to dive deeper into the case.

Can the court system refuse to give me a public defender??

I agree you need to find a private local attorney. Some attorneys take payment plans but get started contacting people immediately.

What do you think the outcome will be honestly and should I get an attorney?

Yes it is legal. I don't believe you need an attorney but if you want your opinion represented more to the district attorney you can hire one.

I completely agree. They need to hire an attorney immediately.

How do I have a charge I didn't know about?

It sounds like you need an attorney if you have a criminal charge at all. I would suggest contacting a local criminal attorney immediately.