iTunes Connect Autofill – Autofill Password Not Working on iTunes Connect

Go to the network preferences, select "Wi-Fi", and click "Advanced..." (you may have to click the lock in the bottom left first). Then, in the "Preferred Networks" list, delete any that you don't want.

The passwords are saved separately, in the keychain. I have verified that removing an SSID from the list in the network preferences doesn't remove it from the keychain, so you can delete them without worrying. (this is unlike the case with iOS, where forgetting a network also forgets the password)

You may also want to uncheck "Remember networks this computer has joined" to prevent them from being re-added when you join them again. Again, this is separate from the "Save password in keychain" that saves the password in the keychain when you enter it.

Since you have shipping apps in the store, you will be able to call developer relations and begin the process to get things reset.

https://developer.apple.com/contact/ and https://developer.apple.com/contact/phone.php

Even consumer Apple ID have the ability to set a separate email address for emails about resetting the security questions and emailing administrative changes, so the account in question might very well be set up in that manner.

While you are on the line, you can ask about setting up multiple accounts for your business so that several people are listed to do certain tasks for you.