Netbackup 7.5 and VDI

Hello,

One of our customer has 2 TB capacity edition, Now they need to include five physical servers hosted (Microsoft  Hyper-V VDI) the size of thess servers around 7 TB. Now should they purchase another 7 TB licesnse or they can Mix the traditional Licenses (Agent for Hyper V) and the capacity Edition ( base platform licenses)

What is the suitable Licenses in this case.

Thanks and Regards,