We use the AFS filesystem, this has something to do with the problem, I can move remote files around in regular unix filesystem space but not AFS space. In AFS file space you need and afs token for permissions, the remote sftp move must be launching a process that does not have a token to do this. I can create and rename remote files as well as copy from the local system to the remote system in AFS file space
using sftp mode.
And can you assign the token to some application/binary?
BTW, I believe that SFTP server does not execute external "move" process. It does it itself.