No, there is no special rate for a disabled veteran through the Turbotax website.
As far as being a USAA member,
To get any sponsored discount such as USAA, you must always enter Turbotax though the special link at your provider's web site. You can not get the discount if you prepare your return using the Turbotax.com web site. See this Turbotax FAQ:
https://ttlc.intuit.com/replies/4652791