There are some problems with how you are attempting to run it. In the working case, the ModelPU is set to resource_local and your JavaServiceFacade starts and commits transactions manually as required. In the non-working case, you seem to be injecting the exact same resource_local persistence context, but not starting/commiting transactions - this is why you do not see updates.
You probably want to be using a JTA context type and the jta-data-source for use with your MbrLevelSessionEJBBean, and you will need to be sure to wrap the appropriate methods within transactions. If not, you will need to change your MbrLevelSessionEJBBean to operate the same as the JavaServiceFacade.
Check http://wiki.eclipse.org/EclipseLink/Examples/JPA for general application server examples and http://wiki.eclipse.org/EclipseLink/Examples/JPA/WebLogic_Web_Tutorial for weblogic specific ones if you want to go the JTA route.