Trying to use sshfs to mount directory from a puppet exec

Ununtu 16.04 and 18.04 (same problem on both)

I am trying to use sshfs to mount a directory on another system, it works fine from the command line but when I execute the same command from a puppet "exec" it appears to succeed but the mount point is not usable:

rful011@secmonprd10:~$ ls -l ~sensors/Rules/
ls: cannot access '/home/sensors/Rules/source': Permission denied
total 4
drwxr-xr-x 2 sensors sensors 4096 Jun  5 13:03 raw
lrwxrwxrwx 1 sensors sensors   33 Aug 21 12:32 sensor -> /usr/local/var/lib/suricata/rules
d????????? ? ?       ?          ?            ? source

where "source" is the directory in question

The command used to mount it is: sshfs -o idmap=user sensors@<host>:Rules/raw /home/sensors/Rules/source

Puppet says the exec succeeded and I can't find anything in the logs to contradict this.

I wonder if sshfs is exepecting some environment vars set?

puppet code:

exec{"rule-source-share":
 command => "sshfs -o idmap=user sensors@<host>:Rules/raw  /home/sensors/Rules/source",
 user => "sensors",
  path        => "/usr/bin:/bin:/usr/local/bin",
  unless => "test -f /home/sensors/Rules/source/updated"
}

The 'unless' is supposed to check if the mount is in place but does not work

Is there a better way to do ensure that the directory is mounted?