Camera offset of chasing model

Hello, I am using lootAtTransform with this code for chasing entity:

          var matrix3Scratch = new Cesium.Matrix3();
          var positionScratch = new Cesium.Cartesian3();
          var orientationScratch = new Cesium.Quaternion();
          function getModelMatrix(entity, time, result) {
              var position = Cesium.Property.getValueOrUndefined(entity.position, time, positionScratch);
              if (!Cesium.defined(position)) {
                  return undefined;
              var orientation = Cesium.Property.getValueOrUndefined(entity.orientation, time, orientationScratch);
              if (!Cesium.defined(orientation)) {
                  result = Cesium.Transforms.eastNorthUpToFixedFrame(position, undefined, result);
              } else {
                  result = Cesium.Matrix4.fromRotationTranslation(Cesium.Matrix3.fromQuaternion(orientation, matrix3Scratch), position, result);
              return result;
              getModelMatrix(currentPositionEntity, viewer.clock.currentTime, scratch);
    , new Cesium.Cartesian3(0.0, 300.0, 700));

There is Sandcastle example
Is there a way to move tracked entity from center to bottom of the screen (same as Google Map app in navigation mode)?