how to open the hood with a dead battery question

[rick3000]

Two other solutions worth trying:
-Check behind the front tow cap, sometimes a dealer or previous owner will route the frunk cable there for easier access.
-Try a cigarette lighter battery maintainer, and let it sit for a few hours

Getting at the cable via the wheel well is difficult enough with the wheel off, that should be a last resort. Have you checked the fuses? Not very familiar with the 997, but if the jumper was providing power to the lights, perhaps a fuse is stopping power from getting to the frunk lock.