Hi!
I am having a similar issue, where the generated Word file is correct but not the PDF.
My client have a custom made font (they are very careful with their visual design) and it might be possible to ask for a re-made font file (with better unicode handling) if that is the issue.
If it is possible for you to check it, the way you did with the Al-Mohanad font, I would be very greatful.
Sincerely,
Göran Roseen