Imari, sorry to hear about your continuing trouble. If you are still working on it, here's a trick I figured out working on my first 'flood salvage' Boxster:
Since you already are familiar with the connections to the Central Locking Unit under the seat...
>Disconnect the blue connector and identify pin number 33.
(top row is pins 1-21 bottom row is 22-42)
>Using a 12v power source (battery), momentarily put the negative to ground and the positive to pin #33.
That will directly apply power to the frunk latch mechanism and open the latch.
