@SueJB version 1 is chunky and elongated half moon shaped whereas version 2 is more tadpole shaped.
But I think the version of the Miaomiao is a red herring as the only difference is the size of the battery.
The Miaomiao does not come with a user manual from new. Your friend has not lost it. The manual is available by scanning the QR code on the box
Have you checked the Libre is still working fine by scanning it with LibreLink?
It is unlikely to be a problem given the failure occurred when you charged the Miaomiao but it is always a good idea to fully discount part of the system when debugging.
The error message is odd. Have you tried asking the xDrip Facebook group exactly what it means? They are incredibly helpful at translating developer speak into user speak You have to request membership of the group but they let me in.
Finally, there is a Miaomiao Facebook group who maybe able to assist. Be warned I found it contained a lot of messages about quality problems.
(Mod edit for clarity)