Hello dear @Malcolm,
thanks for sharing your question with the Wefugees Community.
If your friend is single and is during his asylum procedure and has been living in the initial reception center for the asylum seekers for more than 9 months or is living in a Gemeinschaftsunterkunft for the asylum seekers and refugees or is living in an appartment for more than 3 months, yes he can apply for its permission at his respective Foreigners' Office (Ausländerbehörde), he will get the permission for it. If he is married and has bin living for more than 6 months in the initial reception center or is living in a Gemeinschaftsunterkunft for the asylum seekers and refugees or is living in an appartment for more than 3 months, he can also apply for it and can get the permission for it.
I hope, you have got your answer. I am a MBEON consultant. If you wish to contact me directly, you can see my profile and follow the instructions there.
Best wishes
Fardeen Noori