Yes, there is an error in the map meta data. You can correct it yourself.
Proceed to the step where TransDEM displays the map, but do not convert to UTM.
Now go to the TransDEM temp folder which is usually located at C:\Users\<your user name>\AppData\Local\TransDEM\temp
(You may need to activate the "Show hidden files an folders" option in Windows Explorer.)
Use a text editor to open and edit PA_Harrisburg West_461755_1947_24000_geo.png.aux.xml (for the first file in the series).
Find
Code:
PROJECTION["Transverse_Mercator"]
and replace with
Code:
PROJECTION["Polyconic"]
Save.
In TransDEM, open C:\Users\<your user name>\AppData\Local\TransDEM\temp\PA_Harrisburg West_461755_1947_24000_geo.png and proceed normally including conversion to UTM.