diff --git a/simpeg_drivers-assets/uijson/tile_estimator.ui.json b/simpeg_drivers-assets/uijson/tile_estimator.ui.json
index 6e75671c..2c32aa88 100644
--- a/simpeg_drivers-assets/uijson/tile_estimator.ui.json
+++ b/simpeg_drivers-assets/uijson/tile_estimator.ui.json
@@ -17,5 +17,13 @@
         "main": true,
         "label": "Create plot",
         "value": true
+    },
+    "out_group": {
+        "label": "UIJson group",
+        "value": "",
+        "groupType": "{BB50AC61-A657-4926-9C82-067658E246A0}",
+        "visible": true,
+        "optional": true,
+        "enabled": false
     }
 }
diff --git a/simpeg_drivers/utils/tile_estimate.py b/simpeg_drivers/utils/tile_estimate.py
index d2c2e666..854c754e 100644
--- a/simpeg_drivers/utils/tile_estimate.py
+++ b/simpeg_drivers/utils/tile_estimate.py
@@ -19,7 +19,7 @@
 from geoapps_utils.base import Driver, Options
 from geoapps_utils.utils.numerical import fibonacci_series, fit_circle
 from geoh5py.groups import SimPEGGroup, UIJsonGroup
-from pydantic import field_validator
+from pydantic import ConfigDict, field_validator
 from scipy.interpolate import interp1d
 from tqdm import tqdm
 
@@ -41,6 +41,8 @@ class TileParameters(Options):
     Parameters for the tile estimator.
     """
 
+    model_config = ConfigDict(frozen=False, arbitrary_types_allowed=True)
+
     default_ui_json: ClassVar[Path] = assets_path() / "uijson/tile_estimator.ui.json"
     icon: str = "tilelist"
 
@@ -117,7 +119,6 @@ def run(self) -> SimPEGGroup:
         """
         Run the tile estimator.
         """
-        _ = self.driver.inversion  # Triggers creation of something
         results = self.get_results()
 
         logger.info(
diff --git a/tests/run_tests/driver_tile_estimator_test.py b/tests/run_tests/driver_tile_estimator_test.py
index 9cbef0d2..0b42d1a9 100644
--- a/tests/run_tests/driver_tile_estimator_test.py
+++ b/tests/run_tests/driver_tile_estimator_test.py
@@ -13,7 +13,7 @@
 from pathlib import Path
 
 import numpy as np
-from geoh5py.groups import SimPEGGroup
+from geoh5py.groups import RootGroup, SimPEGGroup
 
 from simpeg_drivers.potential_fields.magnetic_scalar.inversion import (
     MagneticInversionDriver,
@@ -73,8 +73,10 @@ def test_tile_estimator_run(
             starting_model=components.model,
         )
 
-    driver = MagneticInversionDriver(params)
-    tile_params = TileParameters(geoh5=geoh5, simulation=driver.out_group)
+        driver = MagneticInversionDriver(params)
+        tile_params = TileParameters(geoh5=geoh5, simulation=driver.out_group)
+        tile_params.out_group = tile_params.ui_json.to_ui_json_group(workspace=geoh5)
+
     uijson = tile_params.write_ui_json(tmp_path / "tile_estimator.ui.json")
 
     estimator = TileEstimator.start(uijson)
@@ -84,15 +86,16 @@ def test_tile_estimator_run(
         simpeg_group = next(
             group
             for group in geoh5.groups
-            if isinstance(group, SimPEGGroup) and group.uid != driver.out_group.uid
+            if isinstance(group, SimPEGGroup)
+            and not isinstance(group.parent, RootGroup)
         )
         driver = simpeg_group_to_driver(simpeg_group, geoh5)
 
     assert driver.inversion_type == "magnetic scalar"
     assert driver.params.compute.tile_spatial == 3
     assert (
-        len(simpeg_group.children) == 2
-        and simpeg_group.children[0].name == "tile_estimator.png"
+        len(estimator.out_group.children) == 3
+        and estimator.out_group.children[1].name == "tile_estimator.png"
     )