If I add this member to a shared edits group (by changing from Fieldworker to Creator) and by adding this group in the sharing Updates of the survey, then this user can send the survey.
What am I missing?
Shared Updates Groups should not be used for feature editing related; it is for updating content. I would not recommend exploring this as a conventional group for editing or as a means of troubleshooting access.
Can you provide the XLSForms you used?
If you are updating a repeat in an existing survey via the inbox, you need to enable parameters for the record to be edited. The XLSForms will help show what is occurring. e.g. add the below to the esri bind parameter for each begin repeat:
Hi @magisian, thank you for you reply.
the Shared Updates group was just a test to check whether the user could send.
The Survey is part of a group of survey that update in a sequence. the allowUpdates=True is set and it works.
The survey works with some accounts, the only difference I see between those that are working and those that are not is being part of that Shared Updates group.
It doesn't work with the FieldWorker, even though everything seems to be shared correctly.