Good, I see that I've made a new convert 
This seems weird to me: MP3 is an ancient format and the ID3 tag, either in version 1.1 or 2.3, is widely supported across devices. As a last resort, you can try to implement ID3 support yourself by parsing the MP3 binary file itself. The format is extremely well documented all over the web, so it shouldn't be a problem. Try to go for ID3 v. 2.3 first if you can, because it can hold more info and also, it sits at the head of the file, as opposed to the tail, like is the case with v. 1.1, so you don't have to parse the whole audio data to reach it.
Another solution, of course, would be to replace your contraption by a single board computer (like a Raspberry or a Banana Pi) that will be able to take care of everything and read many more formats besides MP3, like FLAC, Vorbis, APE, WavePack, Opus and what have you.