Is this for a Creative Cloud for teams account?
The data and assets will still be there, but you'll need to figure out a way to get to those assets. After the license was transferred, the associated account would have reverted to a free level, with assets still associated with the account. The account would not have been deleted unless that was expressly requested.
As I see it, you may have two options:
1. If you're in contact with your ex-colleague, you could ask them to sign-in to their account. And download/share the assets with you.
2. Or, you may need your IT/mail server admin's help to resurrect the email account temporarily. Perform a password reset to gain access and then download the assets that you need. (That said it may not work in case you're unable to perform a password reset due to 2-factor authentication, password hints etc)
Other than that, I'm afraid, no one else, including Adobe will be able to access assets associated with a user's personal account.