tip #1: advanced storage arrays typically have "modes" for LUNs. i.e. a LUN can be a Solaris mode LUN, or a Windows mode LUN or a Linux mode LUN, and some arrays even have ESXi mode LUNs (but usually a Linux mode LUN is enough for an ESXi host).
tip #2: not all versions of the VDDK in not all versions of NetBackup support multi-pathing - also written as only some versions of some VDDK on some OS for some versions of NetBackup support multi-pathing. And even then you may have to install the correct multi-pathing DSM to support ALUA. If you don't know exactly whether or exactly whether not any of this applies to you then you cannot rule any of it out, and so you really do need to talk to your storage admin team.
tip #3: multi-pathing for NetBackup for VMware host should either:
a) correctly configured
...or:
b) correctly not-configured
...so check the NetBackup documentation.
What this means is:
a) you can use multi-pathing
...or:
b) you should not be attempting to use multi-pathing.
If you do not know the exact correct answer for your combinations of versions hardware (servers, HBAs, switches, storage arrays) and combinations of versions of software (storage array, HBA, firmware, driver. OS, SAN switch fabric OS, ESXi operating system version, DSM version, multi-path driver verison, backup host OS version, etc)... then you need to do your research until you are 100% certain that you can use multi-pathing or 100% certain that you should not use multi-pathing. They are no grey areas. This is a black and white topic.
tip #4: in storage array terms... treat the NetBackup for VMware host (i.e. the Media Server or the Enterprise Client) as if it were just another ESXi host in the ESXi cluster. (assuming multi-pathign is correctly configured or correctly not-configured).