I have a near me widget using a service with a 1-many join. I created the app on AGOL and got it working as expected, showing 1 record for each project found, and when I downloaded and moved to WebAppBuilder and published locally, multiple records show up in search. If a project has 2 joined records, it returns 2 items. If it has 3 records in the join, 3 records are displayed.
So, not sure why the widget on AGOL works as expected but not locally.