FBX export graphics issues

I am having an issue with the graphics for some elements exported to FBX when geolocated using the display origin extents in the view when exporting method which exports the FBX to the correct coordinates, gaps are appearing in some patches I fixed up in context capture as shapes.   When I export the FBX not using this method the patches appear fine, but the model is not geolocated, see below.

has anyone come across this or a solution to fix it?

Georeferenced with gaps:

Non-georeferenced with no gaps: