Welcome to the Wefugees Community and thank you for your question.
If your girlfriend is still in the asylum procedure in the Czech Republic, she will not be allowed to leave the country/travel for the time being. Once she is also recognized, she could visit Germany and marry here. I am not familiar with the regulations on marrying in the Czech Republic, but maybe your partner can contact the local municipality to get some information on the requirements. I am quite sure that they will ask for documents as a birth certificate, a passport and maybe also a proof of no impediment and a residence permit.
In Germany, having a residence permit is not a requirement for the marriage. However, there is a range of documents to be provided as well. For a respective list and more details, please see our blog on this topic.
I hope this helps and please don't hesitate to get back to us with any further questions.
All the best,