score:7
I asked on Twitter and was told to contact them directly through Twitter direct message, attaching a picture of my ticket and the specific request.
After I did so, they confirmed a special meal had been ordered for me. They seemed a little confused about the absence of a 6-letter code but I assumed it would work out, and indeed it did.
Upvote:2
Simple answer, email them. Explain as you did here, they are in the best position to answer your questions.