When I use External_Query, it works great except when I go to call a stored procedure with it:
Can you try below? Removed semicolon inside bracket
SELECT * FROM EXTERNAL_QUERY("cloudsql_instance_name.database_name", "CALL my_stored_procedure()");
Yes, that part is not the issue, I am able to return tables with no problem. when I switch it from "Select * table" to "CALL my_stored_procedure()" I get an error