Currently The ACAD Civil 3D Reader does not fully support all labels. Could all types of labels be added to the reader? Or at the very least, could the documentation be improved to clearly state which types of labels are, or are not supported. The document below alludes to some label support for parcel segments but it isn't very clear.
https://knowledge.safe.com/articles/20153/autodesk-autocad-civil-3d.html
For example, the reader cannot read a pipe label of entity type "AeccDbPipeLabel". Unfortunately, the logging in FME for skipped features is not very informative. It took a lot of sleuthing of FME and Autodesk documentation to figure out why the pipe labels weren't being read. For a list of Autodesk civil 3D label types please see the link below.

