I've seen/managed to get a few 'stuck closed frunks' open with a looooong screwdriver slid in from the side/top under the frunk lid to push the actuating bar on the catch, the part that the cable attaches to. You hafta prise up the top corner of the lid & using some rag to protect the finish, slide the screwdriver (or other looong & thin rigid probe) in from there right across to the middle under the lid edge just below the headlight cowl to where the latch is, then lift the screwdriver handle/lid corner end a touch more so that you can fiddle it around until you get the screwdriver tip in juuust the right spot to push the catch lever that the cable normally pulls, so it is something that really goes against the grain, but it's a method that has worked for me & others and with care, it doesn't seem to be detrimental in the long run. You're only using the inherent flex in the tupperware lid to get the corner up high enough for it to work, so if you're not too ham fisted/bull at a gate with it, the lid generally recovers quickly with no or very little sign you've even been in that way. :thumbup:
I've also seen a frunk opened with a bent coat hanger slid in from the top trailing edge of the lid just above the catch in order to hook on to and operate the catch lever, pretty much like the cable would only from the top instead of the side... but that did end up with a lot of scratches on the edge of the trunk lid, and I'm not sure you could avoid that - maybe with a plastic covered bent coat hanger?? :dontknow:
Anyhow, a couple of ideas that may help, even if just to start the discussion if alternative methods.

Over to you - good luck! :cheers: