SDK Manager 1.6.8170 fails to find target OS for Xavier AGX

Greetings. I fired up SDK Manager (SDKM) on my Mint19.3 host to reflash a Xavier AGX. After putting in Force Recovery, SDKM recognized the Xavier AGX Target automatically. Both my host and the Xavier are plugged into my Gig Switch & internet. It also correctly recognizes the Host OS. However, it Fails to list a Target Operating System in Step 1.
need to Flash 4.5.1 or 4.5. Unfortunately, I cannot use 4.6 for this app.
Is there a way to correct this?

thanks!
-ted

FYI, SDKM is a front end for the actual flash software. Although the basic flash does not particularly care which distribution of Linux is used (so long as it is a desktop PC architecture), the JetPack/SDKM front end wants this to be Ubuntu. I think the most recent SDKM supports an Ubuntu 20.04 host PC, and probably in Q1 2022 this will become mandatory, most of what runs now uses an Ubuntu 18.04 host PC.

Many people have asked about using different distributions, and Mint isn’t that far from Ubuntu, but the easiest way would be to add dual boot into Ubuntu 18.04 (or maybe 20.04 now). VMs are not supported, but they can be made to work if you’re willing to learn how to make the USB correctly pass through. Either way, whether you use a VM or dual boot, make sure you have plenty of extra disk space.