Hello 555-AES.
Thanks for reaching out to Apple Support Communities. If I'm understanding correctly, you are having trouble with unlocking your recently found MacBook Pro because the verification code is not being accepted. I will be glad to assist. Next, I would suggest Contact Apple for support and service as suggested here:
If your Mac is lost or stolen
"How do I unlock my Mac?
After you locate your Mac, you can unlock it with your passcode on iCloud.com. Make sure to use the passcode that you created when you locked it with Find My, not your device passcode.
Here's how to see the passcode that you used to lock your Mac:
- Sign in to icloud.com/find.
- Select your Mac from the Devices menu.
- Select Unlock. After you follow the steps to verify your identity, you'll see the passcode that you need to unlock your Mac.
You can look up your passcode for a limited time. If you forget your passcode or can't verify your identity to see it, take your Mac to an Apple Authorized Service Provider along with your proof of purchase."
Cheers.