Presuming that you're trying to script input into a menu-driven routine to generate data or perform some action, the best course of action would be to analyze the code of the legacy menu routine and see what it is calling to actually generate data or perform the action based on the menu input and have your endpoint call that code directly with the proper inputs from your REST endpoint, bypassing the need for the menu and any scripted input. 

Thank you for the responses so far, I greatly appreciate them!

I found some information online about using ADO and ODBC to make the connection which has gotten me close. Here is what I have in Excel VBA:

and here is the error I get when I run this code:

The "GETSQLLBIMA7" query exists in the USER namespace under the USER package. I'm not sure where "SQLUSER" is coming from or how to specify a different namespace or package.

Thank you both for your responses, I greatly appreciate the help!

I tried going down the ODBC route using ADO based on some other information I have found and I seem to be getting hung up by something not getting specified in the call to Cache through ODBC. Here's what I have in the Excel VBA:

When I try to run this, I get this error:

The Query "GETSQLLBIMA7" exists in the USER namespace under the USER package. I'm not sure how to specify to look under USER rather than SQLUSER when calling Cache.