first of all: congratulations on your marriage!
Do you know the reason why you received the Duldung? A Duldung is in general issued when there are reasons why a deportation is not possible, for example because there is no passport, you are sick, you are about to get married etc. One of the reasons for a Duldung can also be that they give it to you after getting married to bridge the gap until you apply for Aufenthaltserlaubnis. Maybe that was the reason as well for your Duldung and it would be a good thing.
I don´t know all the details of your case but if you and your wife try your best to give the Landratsamt all the documents they want as soon as possible you probably don´t have to be worried right now.
I hope this helps you and feel free to contact me if you have more questions!
Wish you all the best,