Sorry, but you don’t tip for takeout orders. This is the case in every restaurant I’ve ever seen.
For a standard order, I’d agree. For a huge order, likely you’ve never experienced or dealt with. Again, each restaurant has different procedures. Many restaurants add a gratuity to large orders. Apparently Outback did not, yet expected a $2.85 server to do what a manager SHOULD have done. That is their duty, not the server.