The Official doc is the HCL: http://www.symantec.com/docs/TECH76495
The DDOS version is not listed - just NBU and plugin version.
For any possible compatibility issues, you should log a call with Symantec and EMC simultaneously.
Please see this note in the beginning of OST Storage Servers section:
Vendor support considerations:
1. Symantec and OpenStorage server vendors have mutually agreed to support NetBackup customers with OST solutions. Symantec and most OST server vendors are members of TSANet.
2. Symantec qualifies OpenStorage plug-ins for use with NetBackup. The qualified plug-ins are maintained by the party that writes and distributes the plug-ins. Features Symantec Partners implement behind the OST API, that operate independently and are transparent to NetBackup and the OpenStorage API (for example, replication between storage servers, deduplication on the storage server, deduplication-aware plug-ins, data transport mechanisms between the media server and the storage server), are not specifically qualified by Symantec. Partner-specific features designed to interoperate in the NetBackup environment as part of the total solution are the maintenance responsibility of the partner. Check the partner's compatibility list to ensure support of the feature with NetBackup and to ensure that your infrastructure (that is, hardware and network) meets the partner's recommended sizing considerations for the feature.
3. Check the device manufacturer's compatibility list to verify the minimum version of Storage Server software required for your Storage Server family member, that the Storage Server software version you are running is compatible with the plug-in version, and that the storage server software version supports the OpenStorage functionality you are running.
4. Minor versions of the plug-ins listed in the tables below are also supported. (Example: Version "2.0" means versions 2.0.1, 2.0.2, etc. are also supported. Version "3" means versions 3.1, 3.2, etc. are also supported.)
