USB to passthrough VGA display?

[Proximate]

I'm trying to get a physical display on one of the VMs for development work. It would be easier to have a physical machine so I'm trying this first.
In fact, better would be if I could get full KVM control of a vm but I've not found any info on if that's possible or not.

I've connected a usb to vga displaylink device and the vm does see it so I've assigned it to it.
It seems I'm close but I'm also reading it's not possible to do this the way I'm trying to. From what I can understand, it's an issue with the driver.
When I boot the Ubuntu, it does show that there are two screens now but one is disabled.

So in some ways, the driver seems to load but the kernel prevents it from working because it's not a signed driver.
Am I close or is what I'm going not possible or perhaps I need to add a separate graphics card into the host?

# dmesg | grep -iE 'evdi|displaylink'
[    3.968067] usb 2-1: Manufacturer: DisplayLink
[  168.186841] evdi: loading out-of-tree module taints kernel.
[  168.186862] evdi: module verification failed: signature and/or required key missing - tainting kernel
[  168.192041] evdi: [I] Initialising logging on level 4
[  168.192050] evdi: [I] Atomic driver: yes

# lsusb
Bus 003 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 002 Device 002: ID 17e9:0136 DisplayLink DL-195 Adapter
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 0627:0001 Adomax Technology Co., Ltd QEMU USB Tablet
Bus 001 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub

# lsmod | grep evdi
evdi                   81920  0
drm_kms_helper        270336  7 udl,bochs,drm_vram_helper,evdi
drm                   761856  11 udl,drm_kms_helper,bochs,drm_vram_helper,drm_shmem_helper,evdi,drm_ttm_helper,ttm

# lshw -c video
  *-display
       description: VGA compatible controller
       product: bochs-drmdrmfb
       physical id: 2
       bus info: pci@0000:00:02.0
       logical name: /dev/fb0
       version: 02
       width: 32 bits
       clock: 33MHz
       capabilities: vga_controller bus_master rom fb
       configuration: depth=32 driver=bochs-drm latency=0 resolution=1280,800
       resources: irq:0 memory:fc000000-fcffffff memory:fea50000-fea50fff memory:c0000-dffff

# for d in /sys/class/drm/*/status; do echo "$d -> $(cat $d)"; done
/sys/class/drm/card0-Virtual-1/status -> connected
/sys/class/drm/card1-VGA-1/status -> disconnected