I'm having the same issue!
Did you find a solution for this?
Anyone already has a solution for this?
In the end I used a solution I wasn't satisfied with, but at least worked. I used different file names for the resource files I wanted to load and added in the MBean configuration the exact name of the resource to load for that MBean instance, this way the code was able to load the right resource. The problem with this approach is that you have to make sure that all the resource files used this way have different names, so use with a naming convention so that all resource files have a unique name.
P.S. It's been quite a long time so I'm not 100% sure about this answer, but unfortunaly I have no more access to the code I was working with in that period so I hope this solution really works