Form 8879 is not a "confirmation of electronic filing." It's a form that is used to authorize a paid tax preparer to e-file your tax return for you. Form 8879 is not used when you file your tax return yourself with TurboTax. You don't have to authorize yourself to file your own tax return. The person at the insurance company who is asking you for Form 8879 either thinks you paid someone to do your tax return, or doesn't understand how tax returns are filed.
Form 8879 is not included in TurboTax because it is never used when you file your tax return yourself with TurboTax. You could try explaining to the person who's asking for it that you filed by yourself. If that doesn't work, try asking to speak to a supervisor or other higher-level person who knows more about tax return filing. If they still insist on getting Form 8879, consider switching to a competent insurance company.
If you'd rather just make them happy instead of trying to convince them, you might want to consider giving them a fake Form 8879. Download the form from the IRS web site, at this link: Form 8879. Fill in the top part, and parts I and II. Print the filled-in form and sign Part II. Make a photo copy of the signed form and give the copy to whoever is asking for it.
