I have put a question out ton the Geospatial Team as they do all of the Point cloud development in BC/TBC. Based on quick research on the Sketchup Extension warehouse it seems that the Extension you mention requires a RWP (Realworks Project File) in order to work, although it also states that it supports Gridded e57 files, however I dont think we have any way to create a Gridded e57 file either (but I have asked the question internally)
There are also 2 other extensions for Sketchup that may work - one from Undet and another written by D Charlton that state they can import more Point Cloud Formats (that can be exported from BC-HCE (PTS, PTX, RCP etc,)
Take a look on the Sketchup Extension Warehouse and search for Scanner
Maybe you can use those in combination somehow
Alan