Problem:
ArcGIS Pro 3.3.1
3D Tiles dataset from Reality Capture give an error when added into a 3D Scene in ArcGIS Pro.

The diagnostic Monitor Error has the following text
<Event time="Wed Jul 31 14:18:02.572" type="Error" thread="4f0c: Main CIM worker thread" elapsed="0" function="" code="">
3DTiles: In '<not available>': Json parsing error: Missing required field `/root.content.uri`
</Event>
Issue:
The json files exported use 'url', while ArcGIS Pro seems to want 'uri' in the content tags
"url": "tileset_tileset/Geometry/lod9_0.b3dm"
Solution:
Search and replace through the dataset to change url to uri and that allowed the data to load correctly.
Similarly using the 3D Tiles Tools provided by Cesium and run the 'upgrade' function found at the following link fixes the dataset and allows ArcGIS Pro to load the data. https://github.com/CesiumGS/3d-tiles-tools