Yes, DiskDeleter can erase data stored on hard disks in RAID configuration.
A general-purpose driver is installed in DiskDeleter, but depending on a server, the hard disk may not be recognized by a general-purpose driver. In that case, you may need to install a new driver in DiskDeleter so that the server can be correctly recognized and wiped by DiskDeleter.
If your primary use of DiskDeleter is to wipe data on servers, we recommend you request a DiskDeleter evaluation unit so that you can try it out prior to purchase.