This might indicate restrictions on the Project List for users that do not have security access to the Location OBS on the Financial settings subpage.
Is the user able to make changes to the Location OBS Unit through the subpage?
Creating a user-defined portlet may allow the same user to update the data but it may be due to less security access restrictions.
Please be sure to check the Portlet, Options for the 'Attribute Value Protection' (AVP) settings.
Reference the following technical article for more details on the AVP functionality
TEC1272884 : How to Configure AVP Settings to Improve Performance