This is inside the wallet.dat? I don't see any method in forum that you can decode and get the password of xprv?
Also not safe to share your xprv code because i think it includes your seed phrase..
Just quoting this maybe it can help you to recover your wallet
1. Decode the base-64 into binary.
2. Remove the first 16 bytes, they are the IV. The rest is the cyphertext.
3. Derive the encryption key as sha256(sha256(convert_to_utf8(password))).
4. Decrypt they cyphertext with AES-256 in CBC mode using the key, IV, and cyphertext from above.
5. Remove the trailing PKCS7 padding.
This script will do so for you from a wallet file:
https://github.com/gurnec/decrypt_electrum_seedAnother list of recovery methods are here
https://github.com/gurnec/btcrecover