I think it's a good idea to consider Onur's experience in the general context of Germany as a German-speaking country (See - Do you need to speak the local language? www.find-mba.com/board/34713
) rather than in the middle of the refugee crisis. The experience that he, and other international students who don't speak German at a professional level, struggle to find work is not new. I don't understand why he is surprised that there are so few opportunities for people don't speak German.
So, to get back to the choice between HHL and Pforzheim, then I think a third choice has to be be an intenstive year or a semester in a university's DSH programme and then a masters taught in German (Probably in a STEM course http://www.make-it-in-germany.com/en/for-qualified-professionals/working/demanded-professions
). This would be cheaper and more effective if you wanted to move to Germany in order to find work. The Germany language is needed more in managerial roles than in STEM expert roles, since there's less involvement with customers).