Possible to use high voltage servos with Cube Black standard carrier board?

Is it possible power with 7 volts the servo rail on the standard carrier board supplied with the Pixhawk Black Cube? I know it is possible with current ADS-B carrier board but my question is about the older standard carrier board. I would like to use high voltage (7 v) servos.

I have found different advice depending upon source:

This source says Yes: The Cube Black — Copter documentation

This source says No: Hex Cube (Pixhawk 2) · PX4 v1.9.0 User Guide

This source says Maybe with some restrictions: The Cube Module Overview - CubePilot

Which one is correct?