As nobody answered this question I will try to do another workaround:
See this Link:
Anyway: If somebody just knows if it is possible to pack the rar inside the ear in Wildfly, please tell us.
it is possible to pack it inside EAR. but it comes with few limitations
Personally i would go with deploying RA as static module (new module in modules directory)
with extra module with shared code as dependency, on which can also your deploy app depend on.