Doing so you should be able to capture the metadata from all the enumerators. I can guess that some of the enumerators seem to have configured the metadata settings while others seems to have not configured. Kindly please confirm with your enumerators.
But the Person whose details are missing , we had shared two forms with him but in one form, his user name is reflecting where as the one whose screen shot i shared with you , the user name is not reflecting.
If this is the case where in one form his username is there while in the other his username is missing, i guess it’s an admin issue as outlined in the post above. Would you mind checking both these projects and see if you have checked the metadata option in your survey project.