@Stryk3rr3al
“Is it possible to setup a general trunk port as a promiscuous private Vlan port?”
No, it is not. A promiscuous port is basically an access port. What makes it different from a regular access port is that a device connected to it can interface with devices connected to host ports in the same private VLAN.
“Or would I have to pass Vlan 40 directly from the router to the promiscous port for the private vlan?”
Not, necessarily. You should be able to interface with devices connected to promiscuous ports through a regular trunk port. A private VLAN does not restrict access to devices connected to promiscuous ports. Note also that you can have same private VLAN on both sides of a regular trunk. All priviate VLAN rules still apply.