Thanks Joost, as always 
The grades should not be locked inside Moodle in our case, but in Osiris (SIS). We are sending our grades from Moodle to Osiris already.
Key to this idea is: let our teachers/lecturer only work in Moodle and not type in grades in an external system. Feedback/grading should be done in one place: Moodle. From Moodle the grades and feedback can be sent to other systems.
The grades should not be locked inside Moodle in our case, but in Osiris (SIS). We are sending our grades from Moodle to Osiris already.
Key to this idea is: let our teachers/lecturer only work in Moodle and not type in grades in an external system. Feedback/grading should be done in one place: Moodle. From Moodle the grades and feedback can be sent to other systems.