Navisworks will follow the Faro Scene, but will always be later. So you can do two things:
1) upgrade or try-out to the newest Navisworks 2017 and see if your Scene 5.5 is supported. If not, wait
2) Download the trial of Autodesk Recap. That supports Faro clouds and use that to convert the FLS files into a Recap project. (Import, skip registration, Index and save) All versions of Navisworks from 2015 up then can attach the cloud, with better visibility and performance than using FLS files directly in Navisworks.