I think if it were only a matter of taking a long time to delete the account, we wouldn't be so unhappy. To me, the reason your team's behavior seems extremely unprofessional are

1. Not telling Liza when her account would be deleted

2. Telling her her account was deleted but not actually deleting it

3. Sending the "Do you and your friends want to disturb us with this" email

4. Editing Liza's account to claim that she was banned for spamming

Wow! This is the worst excuse for not completing the task that you have promised. It doesn't matter whether she had videos or not, it doesn't matter if anyone visited her profile or not. The only thing that matters is that your customer asked you to delete your account. And all you have done is lie, give excuses and edit her profile page with a vengeance that I (and others) cannot comprehend.