Veeam has an in-guest agent you can use to back up at either a volume or file level. For situations where you absolutely must have physical pass-through devices (like RDMs), this is really the only way you can go about it. For reasons like this, you really need to evaluate why you're using such devices in the first place rather than just using a dedicated physical machine.
Thank you for those thoughts. In this systems case, I added the video card to keep from using CPU during Plex streams. This way I could save resources for the other critical functions this server does like DNS, AD, DC and so on. But like you said this may have just limited me to volume backups, but I really wanted to be able to get a full system(VM) backup for quicker recovery. This however is only a problem in my environment, I will be able to do this at remove locations because they are not using pass-through.