thanks for your quick reply! I'm not quite sure if Promiscuous mode is even an issue for us...
We too have two Aruba Mobility Master VMs with non-working VRRP as soon as they are migrated onto a N-VDS. Tried every option NSX-T has to offer.
Yes, I think it's an issue for you. It's bad design by Aruba to require promiscuous mode, but that's not something you can change :-)
So you need to stick to VDS-based port groups for those VMs. With NSX-T <3.0 this means dedicated pNICS. From NSX-T 3.0 you can at least leverage VDS 7.0 and have everything on the same pNICS without having to collapse the vmkernel adapters into NSX-T (N-VDS).