Yes! I managed to open my trunk this morning. Before breaking down the fascia I tried to open the trunk by the key once more. Just by short key-twists and pushing the trunk down at the same time. After doing so for a minute or so I heard the wonderful 'click'. Was it the overnight rest or the short ride I made yesterday-evening? I'll never know, but it probably gave some space on the arm, which wasn't disconnected from the latch luckily.
One tip for people who might find themselves in the same position one day: I found an interesting article on the miata.net forum:
formatting link
';t 0063 Greetings from The Hague,
Jeroen Feelders
1991 Crystal White Miata The Netherlands
"Jeroen Feelders" schreef in bericht news:3f191bb6$0$49114$ snipped-for-privacy@news.xsall.nl... | While adding a dual-release in the center console the trunk closed | accidentally. 'No problem' I thought. Well, there is a problem. The cable | from the center console release probably removed the arm that goes to the | lock from the latch mechanism. Now what? | | The lock is in place and there's no way I can get the trunk to open... | Hopefully, you've got any idea? | | Jeroen Feelders | 1991 Crystal White Miata | The Netherlands | |