It looks like I'm having a similar problem. I just ordered a new solenoid/actuator (996 511 127 00) from Pelican.
Right now it's hit and miss that the solenoid will activate when I press the remote/button. My issue is what if the solenoid completely fails before the part arrives and I can't open the lid anymore.
The schematics here show an emergency release
Porsche Boxster Lid Parts
Where do I find it ... my guess is somewhere outside the car.
Thanks in advance.
Bobby