Unable to recognize child objects of Java SWT Application

It seems to be a https://eclipse.org/nebula/widgets/grid/grid.php control. If so, you can get data from this grid and interact with it using the grid's internal methods and properties - those under the Java category in the Object Browser.

For example, to get the grid data:

// JScript
var grid = ...; // "path" to your grid object

var nRows = grid.getItemCount();
var nCols = grid.getColumnCount();

var value;
for (var i = 0; i < nRows; i++)
{
  Log.Message("Row " + i);
  for (var j = 0; j < nCols; j++)
  {
    value = grid.getItem(i).getText_2(j).OleValue;
    Log.Message(value);
  }
}

To expand or collapse a row:

gridObj.getItem(index).setExpanded(true);

gridObj.getItem(index).setExpanded(false);