Puzzling - can't find events that are set for other sessions including 10046 in 12.1

I've got a phantom 10046 trace set somewhere but I'm having difficulty finding it. (As the tracefiles only show up on parallel query processes)

I've purposefully set a new 10046 trace on a session that is running a long SQL and it's not being listed/found either.

Here's what I've tried:
1. select sid,serial# from gv$session where nvl(SQL_TRACE,' ') != 'DISABLED' ;
(no rows)
So 10046 doesn't set SQL_TRACE on the session level for gv$session apparently.

2. oradebug
SQL> oradebug setmypid
Statement processed.
SQL> oradebug tracefile_name
/u02/app/oracle/diag/rdbms/sentry_exa_mia/sentry1/trace/sentry1_ora_223206.trc SQL> oradebug eventdump system
Statement processed.