zum, you can try a couple of things...
first, can the application be configured to use another folder to store it's "stuff"? That's the ideal, and I'm sure it occurred to you.
The second - highly unusual - approach would be to make the application's folder in /tmp to be "immutable". I say unusual because while it's not unusual to make things immutable in the filesystem, normally we do not do so in /tmp
If you are concerned with /tmp/path/to/app/folder being removed/cleaned away, you can do
chattr +i /tmp/path/to/app/folder
This means the folder cannot be deleted without first removing the immutable attribute.
If another Unix admin sees that attribute, they will likely remove it from stuff in /tmp... /tmp is often a breeding ground for unux/linix system compromise code.
Hope that helps....
D.E.R. Management - IT Project Management Consulting