Hi Guy Nizry
The error message you saw in the red pop-up is throwing by ArcGIS Online when Survey123 tries to create a feature service view ("_stakeholder") for stakeholders. The message means there's already one feature service view with the same name in your org.
If you cannot find it in your survey folder, it may be moved to other folders accidentally. Please try to search the service view name "survey123_{copied the id from the error message pop-up}_stakeholder" in the upper-right corner search box in the content page of ArcGIS Online. Once you find it, you can just delete it and try to share the survey in the Viewer tab of Collaborate page again.
Please let us know if you still have issue on this, it may need further searching in the service directory of your organization directly by the administrator.