Infraworks Model Repairs
Jeff Bartels of Autodesk shows how to clear the Infraworks TileCache to fix model display and resolve issues.
From the Jeff Bartels YouTube Channel.
and the Civil Immersion blog.
Jeff's post also included a links to an older AKN post How to recover an Infraworks Project with some more processes that might help.
Know your Autodesk product's AppData folder. I do tend try to remember to Duplicate Models at key points.