> We would like to keep logging to a minimal when nothing is wrong with the system
In the case just remove pd4ml.enableDebugInfo() call. If anything fails it prints stack trace independently on the debug mode.
Regarding the fonts: PD4ML has 3 built-in tables of fallback font names for serif, sans and monospaced. It walks the tables when, for example, for Chinese text applied font Arial (however Arial has no Chinese glyphs defined). It is a part of TTF substitution logic.
In your case even Arial is not defined, so it tries to lookup any font is able to display a particular text.