P0A80 Dying battery or Fan issue?

I live in Las Vegas and I’m getting the dreaded hybrid failure engine lights. I have Dr Prius app installed and I’m questioning if it’s the battery dying or an overheating problem or both?

2012 Lexus CT200h, 117,777 miles (yes I tried a slot machine, luck didn’t transfer).

The car has gone limp with the error 4 times in 30 days. Runs only on gas until I clear the code. The code purges after being cleared (tech couldn’t see anything at all when at the shop with tech stream).

Every time it errors, it’s 4-6 pm, using EV mode in very slow traffic or drivethru lane in full sun 105 degrees out. Battery temperature at time of failure in Dr Prius is 115/121/119. Here’s the thing - the blower fan (back seat) is barely audible. I have my AC full blast, cool inside. But battery pack is roasting away while fan does literally nothing.

If I use Dr Prius to override the fan speed to max, the battery doesn’t go above 105 and no errors occur. However, the app has to stay open to keep the setting so this isn’t a realistic solution. Is there something wrong with the computer that it’s allowing battery to fry on low blower setting? It’s running on its own just very low.

I haven’t been to service yet because Vegas just has expensive dealers. Pretty sure it’s just $300 charge and they read the error code and tell me to replace. We have one hybrid shop that’s closed until August - not sure why. I took the car to Greentec Hybrid battery. He’s the one who couldn’t see the code with techstream. Their only diagnostic is to read the code.

When doing the Life Expectancy test in Dr Prius, the battery was slow discharging for the test from “full” down and it errored check hybrid system during the test. I reset the error and went to try again and Dr Prius said “inverter too hot to charge”. Battery temp was over 120 because you can’t control the fan speed while doing the test in the app.

I did the same life expectancy at 2am when it was cooler and got a 44% life expectancy score but it seemed to exit early but no error.

I guess my main question is, does the blower fan in the back really not run at max when at 120 degrees? If so, then I guess I just have a dying battery running hot? What test can I ask to be run to confirm it’s a bad battery because the error code seems to be the only thing they look at? And It looks more like I have a broken system not turning the fan on and frying my battery in the desert?