cannot locate app, locate not working
The launchd job can be run manually so you can see the progress.

Since locate runs find for you, that will also take forever, but perhaps you can inspect the progress or error condition the understand if the locate database is not getting built if you are patient:

time sudo /usr/libexec/locate.updatedb


While that runs, you could try spotlight as it likely has indexed that binary and can report back orders of magnitude faster than the options above:

mdfind "kMDItemFSName == 'gv'"