is causing the LoadError because it is trying to load files from the application folder you have manually deleted, and they are not there. Hence the Error: #<LoadError: cannot load such file – /Applications/ChaosGroup/V-Ray/V-Ray 3.4 for SketchUp/extension/VfS2017>
So delete file: "/Library/Application Support/SketchUp 2017/SketchUp/Plugins/vfs.rb"
… and (if it exists) folder: "/Library/Application Support/SketchUp 2017/SketchUp/Plugins/vfs"
V-Ray is one of those external programs that use it’s own installer EXE on PC and perhaps DMG on Mac. It is usually best to use the uninstall mechanism from the installation. (On PC this would be the Control Panel > Programs and Features).
For such external programs I’d always advise following that program’s instructions for installation and removal.