Context Capture 'Failed to import retouched tile'

Hi Im getting this error when trying to import a touched up tile geometry. I followed these steps to touch up the dgn file that I exported from CC Master (using CC editor)

Im using CC Master Update 15 - version 10.15.0.21 and CC Editor Update 3 - version 10.03.00.23

1. In ContextCapture Master submit a new production – '3D mesh for retouching' and create an DNG (don’t choose Obj) production 
2. Close ContextCapture Master 
3. Open a new blank ContextCapture Editor file (save as dgn in a working folder - we don’t need to keep this file, it is only required to import and export an edited mesh), Import the DGN production (FILE>IMPORT).  
4. Change workflow (toolbar top left) to 'reality modelling' 
5. Under 'View' tab select 'Fit View'. Do this for all three view windows. 
6. Under 'retouch' tab, select 'Delete Mesh Facet'  
7. Select anywhere on the mesh, then with the point, box or line option selected, select the area to remove. Then click anywhere else in white space to delete. 
8. Export file as an DNG (v8) and OVERWRITE the previous version of the retouch DGN  
9. In ContextCapture Master – select 'Reconstruction' of the original model and select the 'Reference Model' tab 
10. Select 'Import Retouches' then select 'Add retouched tiles directory...' - you select the folder and not the file. The software searches in the folder for relevant retouch files. 
11. Select the updated DNG file ('Import retouches) 
12. Submit updates to all productions!  

The unprocessed and processed geometry files (9 and 12) are shown because I re imported the original tiles as I told CC to look at the directory with all my tiles in. 

I dont understand why its failing...