Yes you are finding the same problems as everybody when you are using outside a module, so if you want to do it you should remove embedded libraries and extract them in a directory where you can reference them using load_path (only available in current snapshot).
 But it seems that if you create a JBoss module with asciidoctor and you use that module inside your WAR, it works with doing nothing more. Cool!!! Nice to have this information because we have got many users who uses JBoss.

Thanks