Snapshot errors: backups open stream denied and destinations missing

It seems I am having server permission issues, but I can't seem to figure them out. WPMUDEV Dash is installed from another account, my client's. Please private message me to get the domain name as I want to keep it private.

When trying to run a snapshot, I get this error: Warning: errno:2 fopen(//1490118047_1490118047.log): failed to open stream: Permission denied /opt/bitnami/apps/wordpress/htdocs/wp-content/plugins/snapshot/lib/Snapshot/Helper/Logger.php on line 37

I tried the test suggested here: but it didn't change anything.

Here is a screenshot of the Snapshot settings (see folder permissions error):

Your help is appreciated. We have SSH access and can change file permissions as needed, but I don't know what to change.