Even if it's not, decompilation might be useful. What I'd try is decompiling both the running version and the build of the available source code, and see if the diff is informative.
The goal here is some window into "what changed". For that, we don't need "compilable", and boilerplate won't be an issue provided it's stable (by no means guaranteed, to be sure).
If I had to bet at even odds, I'd bet against it being useful. But the win is potentially large and the effort isn't.
