Johan - yes, core2usb is problematic on some Windows 10 machines and I've seen your failure mode myself.
Stop tearing your hair out. You seem already familiar with Rufus, and I use it for a variety of jobs myself, not just writing iso's in a windows environment. I actually prefer it for formatting sticks as "non bootable", as it really cleans up and formats drives properly.
However many new users may be overwhelmed with the options, not knowing the difference between iso and dd methods.
Therefore the one I recommend for newbs to try is Balena Etcher - especially because it will verify after burn just in case someone got hold of some crappy stick.
That being said, since you already have working *nix systems up and running, why not take advantage of dd available in all of them?
dd if=/path/to/downloaded/tinycorexxx.iso of=/dev/sdX bs=1M status=progress
(Where "X" is the actual device designator, like sdc etc) The old school way to find this was to put in your new target usb stick, and then run dmesg in a terminal to see what it found at the very end.
To be paranoid, shutdown the box, and then remove the drive.
Note that this only recreates a read-only "virtual cd" so to speak so you can kick the tires.
Now comes the second step for TC: you either use the APPS function to download and run tc-installer.tcz and use THAT to write yet another stick - which properly writes TC with it's unique requirements properly. That is your working stick.
OR if you choose the CorePlus iso, that already contains a bunch of other stuff, including the installer right in the menu bar. Use that to make your secondary daily-driver stick.
Since you mentioned using Windows 10, for the 32-bit version of TC to work, the computer should of course have secure-boot disabled, and also be able to function with "legacy" modes - adjustable inside the so-called bios setup.
Hth - you've wasted waaay too much time on core2usb. Use the dd command in your existing linux distributions..