by Juan Leyva.
Hi,
as far as I know this Web Service is just for getting generic/standard/common information about a module (all the moodle modules has some fields that are mandatory), you are not going to be able to find specific information for a module (like the link to the SCORM zip package).
We are developing Web Services specific for getting modules information (like mod_data_get_databases_by_courses and mod_forum_get_forums_by_courses)
Regarding availability information, "Modules availability" should be enabled at site and the course level and the user you are using for requesting the information via web services should have permissions (teacher or admin) to see the module settings
Cheers, Juan