As already informed above in this thread, the new Vegas' fonts are stored in the folder:
C:\Program Files\VEGAS\VEGAS Pro 18.0\fonts
You can navigate to that folder to see all the fonts names you are looking for. Although the fonts are stored in that folder, Vegas automatically installed them in C:\Windows\Fonts. The fonts don't appear with a "new" prefix in Vegas because they are fonts licensed by Vegas (not developed by) and have their own metadata information that is read by the system. This is the default behavior for any other font installed by any other application. This is not a Vegas shortcoming.
@VEGASDerek, it would be informative to add in Vegas 18 release notes the font's names:
C:\Program Files\VEGAS\VEGAS Pro 18.0\readme\Vegas_readme.htm
For general information, I just copied the font names and here they are:
I've never seen anywhere anytime where fonts are named new or old. They are just fonts no matter what program/app they appear within and no matter at what point in time they are introduced.