Attendant secrecy

[DTDude]

In LD 15, I have the SYA option set. When a DN is dialed from the console while on an outside call, the source is automatically excluded and hears MOH as expected. However, when an internal call is transferred the source is not automatically excluded, and both source and destination hear everything.

Is there a setting I missed, or is this as intended?

 

[KCFLHRC]

Feature description
Attendant Secrecy automatically prevents a voice connection between the
source and destination parties of a call being extended by an attendant,
until the attendant connects the two parties. This allows the attendant
to converse privately with the destination party before completing the
connection. Attendant Secrecy is allowed or denied on a customer basis.
Operating parameters
Attendant Secrecy is available on attendant consoles only.
Attendant Secrecy operates only on external calls received from an outside
trunk (for example, Central Office or WATS trunks).