It is of course possible to change this permission but inadvisable.
The basic principle here is that root is NOT to be used as a regular user. You only login as root to perform security sensitive operations such as system upgrades. Therefore anything you must do as root should not in general be viewable by other users.
On that bases root's working area ...
Your ghoststart.sh script (or the cyberghostvpn thing within it) is trying to start OpenVPN by calling the openvpn executable. This executable is not found in the $PATH within the script. Use command -v openvpn in a terminal to locate the path of the executable.
If your openvpn executable is located in /usr/sbin, you may write your crontab schedule as
The login failed, because there is no setting for PermitRootLogin in /etc/ssh/sshd_config which defaults to prohibit-password, which means password login is disabled for root.
to the Match block would allow root to login with password or public key authentication.
Another option would be to use a different user.
Your user's PATH environment variable does not contain the path where these files are located. When you use su -, root's environment variables get loaded into your session. See man su:
-, -l, --login
Start the shell as a login shell with an environment similar
to a real login:
o clears all the environment variables ...
From your last example, it looks like your non-root username is t.
When you use ssh, scp or rsync and don't specify a remote username, the tools will assume that the remote username is the same as the local one. So the command in your first example:
rsync -a --delete --stats -h wget 'olive:/tmp'
could be written more explicitly as:
rsync -a --delete --...