Adamant1
Looks like it is the department of housing. Which is essentially inside the park because they purchased the land a while ago and was going to turn it into public apartments or something, but it fell through. So now its government offices, but the park is still there around it. Here is an official for reference, there's a lot of other ones to that can be found by searching for the parks name and the word map. Oh yeah, I added a commercial area for the offices based on the map. https://www.raleighnc.gov/content/ParksRec/Documents/DorotheaDixPark.pdf