Well obviously. But often those are typical issues you'd find for the model as they age. And he managed to buy 2 non-running i3s where the rex also wouldn't start. Cars not even that old yet.
I think the issue in the end wasn't even the rex, but the rex refuses to start if the stars aren't aligned. And if you're in the NA market then you can't even start it manually so you can only troubleshoot it by running the battery nearly flat when it's acting up. Which is why imo it's not a great extra and I'd rather take another car with a bigger battery if the extra range from the rex is crucial. The rex system had to be compromised for the car to retain its title as a BEV rather than a PHEV.