2006 Prius Hybrid battery fail ?

I would like to know your suggestions on my next step.

Story:
One evening, I forgot to close the left rear door properly and didn't touch the car for 2 weeks straight. I tried to open the door but it refused to open, car wouldn't turn ON. I thought the 12V battery died, so tried jumping but the latch was broken. I called AAA and got the car towed to their certified mechanic shop.
The guy at the shop replaced the 12V battery, latch was working - charged me 450$ (battery cost and 1.5 hr labor for diagnostics and battery change) and he recommended things that I should have done before (recently had a new born, I was super busy) - tune up, brakes and oil change. I know I was due for an oil as I drove 6000 miles after the last oil change and it was well over a year ago.
He did his customary test drive and asked me to pick it up this afternoon.
I picked up the car, drove 0.5 miles and the car died on me, when I started the car no error codes but when the car died on me, it had big warning light, hybrid battery symbol and brake symbol. I noticed the hybrid battery was never getting charged, I called AAA and got it towed it back to the mechanic.
Mechanic after evaluating for 1 more hour (150$) says that hybrid battery is dead and quoted me the price of the battery and 6 hours of labor for replacing it or take the car back. I called AAA and got it towed back home. In all I paid 600$ and the car is now dead, don't know what my next step...
Mechanic also mentioned that the error code is P3190 and that could be a lot of things.

Car right now turns ON but wouldn't go to drive gear but stays at neutral.

Kindly suggest my next step - should I get this car to a dealer or any other mechanic for a second opinion or just send it a junkyard (it has brand new 12V battery). I feel frustrated.

Thanks,
Veeru

 

Car details: Bought in 2017 when the car had just under 100K miles, current odometer reading is 131K. According to carfax, the previous owner had the hybrid changed in 2012 when the car had 70K miles.

Mechanic quoted 3300$ for the battery and 900$ for labor.

 

Thank you so much for your detailed reply. It wasn't AAA mechanic but AAA certified shop. Is there any good prius indy in north jersey?
I would call the local toyota dealer and see what they recommend but I doubt they would be cheaper than buying a new one...

I created an account on toyota and verified that the hybrid battery was indeed replaced by them around 70000 miles in 2012. I didn't know that you could track all the records, it was nice to see. I usually do my oil and filter changes with them and I see all the records in addition to my account on the local dealer website.

Do you recommend any OBD device to check the codes myself?

Thank you so much again for taking time and replying to my post. It is really frustrating, I don't think the AAA certified shop was trying to con me or anything, I am just frustrated that without any warning signs, how could the hybrid battery die? This shop has been active for 26+ years and it was the owner of the shop who worked on it, so can't doubt him.

 

Thank you for your comment and very nice explanation of what could have happened.
Mechanic said he drove on the high way for about 10 -15 mins and asked me to pick it up, I picked up the car and car engine died on me within half a mile from the shop and it seems we have driven the car on the hybrid battery. Now the car wouldn't go into drive mode and the mechanic said the hybrid battery died and I wondered how it could die without showing any symptoms. I got 55 MPG in April. Is the battery completely dead now ? When the car died, it showed hybrid battery symbol and the triangle of death. Does this mean the HV battery died completely?

 

Thank you SFO, TMR-JWAP, mr_guy_mann for taking time to reply to my queries.

The car starts without any problem but doesn't go to drive mode. The hybrid battery is at 1 bar and I noticed that when I was driving from the shop, hybrid battery wasn't charging at all and when it died, it showed the red triangle and hybrid battery failure symbol. It very well could be that mechanic (AAA recommended shop) didn't know what to do when he saw the car wouldn't start, he just replaced it with a brand new 12V battery and thought everything else falls into place automatically.
He told me the error code was P3190 (he mentioned it on the invoice of my 600$ payment). I am getting the car towed to the local dealer on Monday and hopefully the diagnosis is not the failure of hybrid battery.

I will keep you guys posted. Thank you so much again. Have a good weekend.

 

Update: Dealer checked that the hybrid battery was completely drained but nothing wrong with the battery itself. Car is now revived, no codes and everything seems to work fine. Dealer charged 272$ plus tax for charging up the hybrid battery and reset the system.
I also had requested a tuneup, oil change and fuel injector cleaning and throttle body cleaning. Dealer checked hybrid battery system and found no issues either but cautioned me to never let the prius sit idle for more than a week.
Thank you so much guys , I am glad, I didn't junk the car and went to the dealer.