There are two possible solutions to this issue:

Solution 1:
Make sure to clear out the cache folder of any old files after sending the CC character to ZBrush and before using GoZ to CC (Preferences > GoZ > Clear cache files). Under the current GoZ system, the presence of old cache files will attach sequential numbers on the subtools, causing them to be mis-read and unable to be identified.

Solution 2:
Make sure the ZBrush subtools and the CC mesh names are consistent. If not, please give the same names to the corresponding items.