A previously completed bug described here: https://feedback.telerik.com/aspnet-mvc/1476295-moving-files-can-result-in-permanent-deletion seems to have resulted in code that has the potential to delete ALL files if moved a few times.
I have not had a chance to get the latest version since the above mentioned bug was marked as completed, but I have made a couple of attempts to test the new functionality in your Demo system on this page: https://demos.telerik.com/aspnet-mvc/filemanager
Repeating the previous test, I have now found that a few move actions results in what appears at first to be a Copy, rather than a Move, but then a subsequent refresh reveals ALL files have been deleted.
Steps to reproduce on the Demo system:
I found that after repeating, the files did not appear to move, but seemed had been copied. But a refresh of the Demo page shows that all images had been deleted.
Following the above, here are a couple of screenshots: