You can try handling the QueryCellStyleInfo event.
Private Sub GridGroupingControl1_QueryCellStyleInfo(ByVal sender As Object, ByVal e As Syncfusion.Windows.Forms.Grid.Grouping.GridTableCellStyleInfoEventArgs) Handles GridGroupingControl1.QueryCellStyleInfo
''make "Col1" readonly if "Col0" is the not the empty string
If Not (e.TableCellIdentity.Column Is Nothing) AndAlso e.TableCellIdentity.Column.Name = "Col1" Then
If e.TableCellIdentity.DisplayElement.GetType() Is GetType(GridRecordRow) Then
Dim rec As GridRecordRow = e.TableCellIdentity.DisplayElement
Dim o1 As Object = rec.GetData()
If Not o1 Is Nothing AndAlso o1.GetType() Is GetType(DataRowView) Then
Dim drv As DataRowView = o1
Dim o As Object = drv("Col0")
If Not (o Is Nothing) And o.ToString().Length > 0 Then
e.Style.ReadOnly = True
e.Style.BackColor = Color.LightGoldenrodYellow
End If
End If
End If
End If
End Sub