Hi Mia,
I have been meaning to get back here for a while.
I didn't get a solution, but I did get a work-around using a couple of other modules - configurable reports and Flatfile enrolments.
I created a SQL report within config reports with the following code. If there are only a couple of people, I just manually add them. Any more than about 4, then I export the results, remove the header row and first column, save it as a csv, and upload it using the flat file upload. (Note - I modified it to read the staff number and course number - seemed a bit daft to have an item which you put in manually to do a bulk upload.)
So I run this on a daily basis, and no issues with lack of enrollments.
SELECT w.name, 'add', 'staff', w.login, w.courseid
FROM
(select CONCAT(u.firstname, ' ', u.lastname) AS Name,u.id as id, u.username AS login,e.courseid as courseid, e.status as status
from prefix_user AS u
INNER JOIN
prefix_user_enrolments AS ue
on u.id=ue.userid
INNER JOIN
prefix_enrol AS e
ON e.id=ue.enrolid)AS w
LEFT JOIN
(SELECT u.id AS id2, ct.instanceid AS iid, ra.roleid AS rid
FROM prefix_user AS u
INNER JOIN
prefix_role_assignments AS ra
on u.id = ra.userid
INNER JOIN
prefix_context AS ct
ON ct.id = ra.contextid) AS v
ON w.id=v.id2 AND w.courseid=v.iid
WHERE v.rid IS NULL
Pretty simple really.... :D
Cheers
Peter