They will allow it, but why not just advise them of the issue and include it in their audit report?
Also, if you want to discuss your letter with anyone at TurboTax, they have a free Audit Support Center you can phone during business hours. At the link below, click on the blue "Get Help" button, then answer a couple of questions, and it will show you the phone number to use.
<a rel="nofollow" target="_blank" href="https://support.turbotax.intuit.com/irs-notice/audit-support">https://support.turbotax.intuit.com/irs-notice/audit-support</a>
If you bought the Audit Defense product when you filed, see this:
<a rel="nofollow" target="_blank" href="https://ttlc.intuit.com/questions/2924451-i-bought-max-or-audit-defense-and-now-i-m-being-audited">https://ttlc.intuit.com/questions/2924451-i-bought-max-or-audit-defense-and-now-i-m-being-audited</a>