I spent a little time looking at this new suction motor and noted the electrical plug has 8 pins - so this leads me to believe when you pull the release cable it connects electrically to the primary and secondary release actuators - and makes sense, however, the lack of a mechanical link would mean if either actuator failed or perhaps the 12 volt battery in the car fails then the release lever wont do anything - or in your case an internal fault with the control box or suction motor will result in the emergency release cable being inoperative.
When i get back I will install my kit but I am also going to add two more cables - one to each actuator and put those cables into the wheel arch area either side- maybe just tucked into the arch liner, just two bicycle brake cables should do it - and hopefully I will never need them but i will have a mechanical link to ensure I can never be locked out of the frunk.