P0AFA code only on Prius bought 3 weeks ago

Hey all, new to the forums, trying to figure out my best route here.

I bought my 2008 Prius base with 170k miles on it 3 weeks ago; a refurbished hybrid battery was installed ~7 weeks ago. I drove to a city 180+ miles away for the car. The hybrid battery has a remaining 4 months warranty, but the shop is run by a single guy, he doesn't even have a website for his hybrid repair shop. I'm a little nervous about the logistics of trying to get any repair work done from him. I really wouldn't want to tow my car 180+ miles away when I have a specialized hybrid mechanic less than 5 miles away from where I live. I don't know if I could convince him to drive down to me, but even then he doesn't have any space to work on my car where I live.

As for the actual problem, the car has been driving fine until yesterday. I didn't drive it for about a week, and was greeted by a check engine light and a red triangle. I was able to drive the car to AutoZone to get the P0AFA code. I could tell the hybrid battery wasn't functioning during my short drive; no regenerative braking, engine was on the entire time. From searching these forums, Reddit, and YouTube it looks like the likely problem is with corrosion on the pins with the hybrid battery ECU. I reached out to the specialized hybrid mechanic near me, I let them know the code I had and asked what they thought of it being a problem with the ECU. They said it could be a number of problems, and didn't want to speculate until they could look at the car which is fair, they're the professionals.

They can't look at my car for 3 weeks, which is my biggest frustration. I CAN go without my car for 3 weeks, but I really would prefer not to. I'm assuming it's not a good idea to just keep driving my car with this problem. I'm of course stressed this could end up being a really expensive repair.

I did get a bluetooth OBDII reader to use with Dr. Prius, but I definitely don't fully understand what I'm looking at hah.