Hello @Msk2000
Nice to hear from you again.
As far as I know, there is no such thing as a study ban for Saudi Arabians. There is a number of requirements your friend needs to fulfil in order to study at a German university, but nationality is not one of them.
Please check out the following website to find extensive information about studying in Germany as a refugee:
https://***.study-in.de/refugees/studying/requirements/studying-as-a-refugee_53906.php
Best regards,
Thorgen