Welcome back to the Wefugees Community and thank you for reaching out to us again.
Is there any specific reason why you want to get married in France? As long as you are in a pending asylum procedure in Germany, you are unfortunately not allowed to leave the country. The same would apply when you are holding a Duldung. In case you are holding a valid residence permit, you may travel freely for up to 90 days within the EU. I am not really familiar with the Wedding procedure and regulations in France. I tried to make some research and I read here, for example, that people who want to marry in France need a residence permit there as well. In case you manage to marry in France, I assume you would't face difficulties with the acknowledgement in Germany.
For more information on marrying in Germany though, you could check our blog on this topic.
Regarding the family reunification visa: Yes, it may happen that the German authorities ask you to apply at the German embassy in your country of origin. In this case, you need to give them a good proof why it would not be reasonable for you to travel back and to be seperated from your partner and life in Germany for a longer period.
I hope this helps and please don't hesitate to get back to us with any further questions.
All the best,