When you add a queue member, the label on the manager has no relevance at all. If you want to trace the issue, you will have to start fop2 in debug mode and capture events, and look for "rename" events and what happens BEFORE you see those.
service fop2 stop
cd /usr/local/fop2
script capture.log
./fop2_server -X 511
(log into fop2, wait for the label renaming/change)
ctrl-C
exit
service fop2 start
Now you have a capture.log file to check for.
Best regards,
