If you are sure that currently no other process does perform redefinition of this table you can call DBMS_REDEFINITION.ABORT_REDEF_TABLE procedure and after that drop the interim table (brtools create it as original table with $ at the end). After that you can start reorganization again. For more info:
http://docs.oracle.com/cd/E11882_01/server.112/e25494/tables007.htm#i1006856
http://docs.oracle.com/cd/B19306_01/appdev.102/b14258/d_redefi.htm#i998327