Did you try the low-tech approach, a course-wise transfer?
https://docs.moodle.org/26/en/Course_backup
https://docs.moodle.org/26/en/Course_restore
Re: Merging multiple old (2.6.2+) instances into a single new (3.5.1+) one
by Visvanath Ratnaweera -
Number of replies: 0