Is this because you are working with a virtual proxy and hotadd transport mode? nbd should be able to use ESX host networking to get you the files you need, without the need for a VADP proxy per un-shared datastore.
I'm also finding the new VADP limitations to be a step backwards from VCB. The biggest gripe is the new proxy must reside on a node that has access to the datastores, in our environment we use only Linux servers on standalone ESX Hosts within a DMZ infrastructure... where VCB allowed us to backup all the Linux VMs across all 10 ESX Hosts with a simple firewall change and one single VCB Proxy, now we are expected to create 10 Windows VADP Proxy servers, one on each ESX Host and create a bunch of firewall changes for each of the Windows VADP proxies. This is a major step backwards.
Internally we also run numerous clusters, so now a new Windows VADP Proxy server must be configured on every Cluster... another 8 VADP Proxies! So where we had 1 VCB before, now we need 18 VADP Proxies! Thats just nuts!