Dead puppy

Looks like a dead 12v battery to me.

 

Sounds like a dead battery. Kind of early for it to just die, a light was probably left on.
I don't have a Gen3 to compare to, but I would say that the missing fuses are fine. They're probably for an option your car doesn't have or just extra spots Toyota left for future options in later models.

 

Hope AAA is careful, if they hook up the jump wrong say good bye to a lot of money. I would have the manual out to the section for jumpstarting the car and show it to the AAA guy…Good Luck

 

When my 12v battery kicked the bucket I made sure I was ready for the AAA guy. I had to fight with him because he wanted to jump the car from the battery and it required me showing him the manual to get him to listen.

 

You can jump it using that Red clip there and a ground. You don't need to open the rear trunk where the battery is at to jump start the Prius.

If you look at mark's image, you can see there's that red tab, you lift that red tab and its the positive terminal for the battery, you can hook the red on your jumper cable to there and the black to any solid ground on your Prius, usually the engine mount bolt or some hard ground and you can jump the Prius that way.

 

Battery or jump terminal, it doesn't really matter. The only thing that matters is that you hook it up with the correct polarity.

 

At 50,000 miles on a 2011...after a full discharge like that...replace the 12VDC battery now. It's days are limited.

 

To the OP, don't just focus on the jump start. Especially with the Prius' diminutive 12 volt battery, a partial drain will set it back. Jump start will get you going, and driving around will help, but you should look into an intelligent battery charger. Minimum overnight hook up is likely warranted. Get one with status lights. Check in the owners manual: there's an amperage limit, around 4? It's a smallish battery.

A digital multimeter is also handy: a 100% battery should read 12.6 volt or higher. Readings taken just after charging will be inflated. You need to drive it for a few days before checking.

Or go with frodoz' recommendation..., still, if you have the tools I'd give it a try to resurrect it. But start window shopping for a replacement.

BTW, don't give up your day job to become a mechanic, LOL. After all the description in your first post you say you doubt it's the battery causing problems?