Found the ARM building instructions - they really do look similar to what I did, so I'm glad I didn't take a path that was totally ludicrous.
For people that might be looking at this down the line, pallas' Diamond wallet ARM build instructions and headless binary are linked in his post here: https://bitcointalksearch.org/topic/m.8380165 ! It even has a nifty donation address for his work.
Is there any chance you know the reason your additions (and the boost scopes that I missed, though it looks like the file just uses the namespace, so maybe they're no longer necessary?) haven't been picked up in the official repo? It didn't look like danbi was being too responsive on the matter and I got tired of flipping through the thread to look for the conversation really quickly (and just looked through your past posts to find your instructions/build).
Also, do you have a Git/SVN/Mercurial/whatever repo that you maintain for your builds? If you do, I'm going to delete my fork and follow yours, even if it's not linked to the DMDcoin GitHub.
And, finally, sorry for stepping on your toes if you were affronted.
EDIT: clarification of boost scope/namespace usage