1IM 8.1.2: More than 8000 Localities in one layer: Object Selection failing

We've got a huge, but plain list of Localities (no hierarchy). It contains way more than 10.000 entries. 

We've come accross the issue that in the Web, the standard component VI_ObjectCollection_Hierarchical is used to select a Locality. But that implementation fails if there is one single node in the tree that contains more than 8000 entries: 

2020-09-23 13:07:36.8136 ERROR (    WebLog ps1rie2yzia2ah3yi2cy1smv) : VI.Base.ViException: Beim Ausführen der Formularmethode Popup2_Popup2_ControlRef1_Container6_TableSwitchContainer2_Container2_TreeBand1_DataSource ist ein Fehler aufgetreten. ---> System.AggregateException: Mindestens ein Fehler ist aufgetreten. ---> VI.DB.InClauseLimitException: Die IN-Klausel überschreitet die Grenze von 8000 Elementen. Verändern Sie die Abfrage.
   bei VI.DB.DataAccess.SqlFormatterBase.FormatInClauseInternal(String columnName, ValType theType, FormatterOptions options, IEnumerable values)
   bei VI.DB.DataAccess.SqlFormatterBase.InClause(String columnName, ValType theType, FormatterOptions options, IEnumerable values)
   bei VI.WebRuntime.Data.DbDataSource.<CanHaveChildrenAsync>d__31.MoveNext()

We don't need the hierarchical selection in that case. Is there any way to disable this for Localities? I tried to remove the entry in Object-dependent references->ObjectCollection for Locality, but it's telling me that I'm not allowed to modify default objects or assignments. What can I do?