Jarczak’s fork crossed the line by injecting falsified identity metadata into its network communication. “In simple terms: it pretended to be the official Bambu Studio client when communicating with our servers.”
If it's easy enough to get access to your cloud infrastructure by just changing some metadata about the connection, then you really should re-think your authentication systems. If I were to publish the exact model and pinning of the lock on my house, it would be silly of me to be mad that someone used that to make their own keys.