In the Vegas "Render As" menu, make sure you have "Show Favorites Only" de-selected.
If neither Voukoder nor VoukoderPro works on your rig, there's something screwy with your system settings. Lots of successful users with Vegas 21.
Your vRender times are 100x higher (slower) than mine.... and my system is not new. Some of your vRender times (the time Vegas takes to render the frame before it gets fed into Voukoder/VoPro) are over 1 second, which is bonkers. On a system like yours, I'd expect at least double-digit fps . . . not <1 fps.
Are you trying to run any other programs at the same time (e.g., mining?), or is Vegas running out of RAM? To be clear, you're saying that all projects malfunction, without exception? Have you tried creating a simple new project and rendering that?