@kallum-redgrave I recomend to do an unattended installation of fog-client from the setupcomplete.cmd instead install it on the image:
https://docs.fogproject.org/en/latest/getting_started/install_fog_client.html
and execute this commands, after installation:
sc.exe config FOGService start=delayed-auto
sc.exe failure FOGService actions= restart/60000/restart/60000/restart/ reset= 120
net start fogservice
this configure the service to start delayed and restart on failure.