We are experience the same issue described on this post https://moodle.org/mod/forum/discuss.php?d=241754

Hi,

A colleague has reported what seems to be a bug in how group assignments are handled by Moodle 2.5.2, when all student group members are required to submit.

To replicate the bug:

Create groups in a course (for example, two groups with two students in each group)
Add an assignment to the course, with the following parameters:
Submission types: select File submissions
Under Submission settings:

• Require students click submit button: Yes
  Under Group submission settings:
• Students submit in groups: Yes
• Require all group members submit: Yes

Now, connect using Student #1 in Group #1 and upload a file. First clue there is something weird going on: there is no button to submit the assignment for grading.

Connect as Student #2 in Group #1: a submit button is present. Click on the button to submit.

Lastly, connect again as Student #1 in Group #1. There is (still) no submit button to be seen.

The teacher's view is telling:

• The "Status" column shows that team members have submitted for grading, but not the original file uploader;
• The "Group submission" column says "Draft (not submitted)" for all students;
• Files are visible for all students under the "File submissions" column.

Anyone have a clue on what is going on and how to fix it?

Thanks in advance.