You needed /home/username/googledrive not /home/googledrive
You don’t need any quotes unless “/path/to/googledrive” contains any spaces or other special characters that the shell might interpret. * & $ # ! ( ) { } [ ] " ’ ` < > ? ; \ | all have meanings to the shell and need to be not onlyt quoted but escaped if you have a directory or filename that includes one of those characters.
No matter what, you don’t want quotes around the entire command. That tells the shell to look for a file named “something [space] /path/to/foo”, and try to execute it with no arguments. There is no such program of course. 
There is a program called “something” and you want to execute THAT with an argument of “/path/to/foo”
One thing I do not know myself yet because I have not tested yet: What happens if wifi isn’t working until long after the desktop session is started? IE, you start the desktop session, but there is no network until you log in to the captive portal at a coffee shop. But google-drive-ocamlfuse was executed right away as soon as you entered your pasword. Does it fail and thats that? or does it stay running even though it failed, and retry every 60 seconds regardless if the network is up or down, and then later when the network is up it just starts working? That could be one reason this might not work for some people sometimes yet work for other people other times, purely by the luck of the timing of how fast different things happen.