Thanks for the help. I, too, thought it was the Brandenburg in Germany. I'm still not too positive that it is, however. I had a look at a couple of gazetteers, one from 1794 written in English and another from 1840 written in Dutch. Just for reference, the marriage took place in 1746. (I haven't been able to find a gazetteer from an earlier period, but that doesn't mean that they don't exist.)
The 1794 version, which is a gazetteer of the Netherlands, has two entries for Brandenburg: (1) a village in the province of Limbourg 20 leagues south from Aix-la-Chappelle [nowadays known as Aachen in Germany]; and (2) a town of Luxenbourg.
The 1840 version is a general gazetteer. It also has two entries: (1) a town in Luxembourg; and (2) a former town in the province of Groningen.
I may be able to lean towards what you said, but I have noticed that whenever a person is from a different location, they typically list the province (if in the Netherlands), or the county (if outside of the county). If what you say is true, then Brandenburg, Germany is the first exception I've seen.
Perhaps I should contact a Dutch historical geographer to see if maybe a Brandenburg was a town that is now non-existent. Any suggestions?