If you want to turn on LDAP tracing from the OnDemand side on z/OS, try this:
//ARSSOCKX PROC
//ARSSOCKX EXEC PGM=ARSSOCKD,REGION=0M,TIME=NOLIMIT,
// PARM=('ENVAR(LDAP_DEBUG=2147483647)/-S -I ARCHIVE -v')
I don't have any real experience with this, just know that it should work.
Ed