The private key and certs are further obfuscated, to get cleartext you need to do: Encrypted string from cy() -> ure(string, key) -> RC4 decryption -> decodeURIComponent() -> final string.
Example Python reimplementation to extract the secrets, easy to run. Copy the content of t from function cy() in main.js and paste it here. After running, you have a private key from Bambu Lab.