What computer operating system is your Premiere Elements 12 running on? Just background information, just in case.
If you have added and installed new "Windows TTF fonts" and only some of them show up in Premiere Elements 12, you apparently
know how to install fonts into Windows.
The Premiere Elements Titler is particular sensitive to how a particular font is written. As far as I can determine there is nothing to be
done when the Windows installed font is not available to Premiere Elements, except to look for a similar font which the Premiere Elements Titler will recognize.
Is there anything particularly unique between those fonts that do appear in the Premiere Elements Titler and those that do not?
I will think about this some more.