Or you can look at V$SQL.BIND_DATA or possibly V$SQL_PLAN.OTHER_XML although I'm unsure at what version the peeked binds appear in the latter.
select * from table(dbms_xplan.display_cursor('<sql_id>','<child no>','+PEEKED_BINDS'));
In this case, any idea why did the optimiser decided to choose the bad plan instead?maybe the index was unusable. maybe the stats changed. maybe data changed. how are we supposed to know without having any evidence?