Can't delete font files

I have 3 font files on my desktop that I placed there temporarily to do some testing with them. I installed them "temporarily" using suitcase fusion.
However, since then I am not able to delete those fonts from my computer. Suitcase fusion shows that they are not activated, and I have no programs open (after a fresh restart) and I can't delete those files.
In control panel > fonts window, these fonts are shown with a shortcut arrow symbol on them (what does that mean?). I used nirsoft's "open files viewer" to see if they were open and they are shown to be open, and the process is shown as "System process"

What can I do to delete these font files?
(Using Windows 10 Pro 64 bit)

Thanks,
David