Can you send a screenshot of the encounter pbs? In addition, have you tried multiple type of encounters to see if any of them work, like fishing/surfing/cave etc?
Which type of encounter isn't working? What version of essentials are you using? Do you have a Cave type encounter and a Land type encounter on the same map? (which doesn't work in v19.1 at least.) Are the Pokemon you are attempting to spawn fakemons, if so are they set up correctly in the pbs?
Did your encounters work before installing EBDX? Is it all maps you make that don't work, or one specific map? If you've only tried one map, make a quick test map to try there.
In short, theres a million troubleshooting things we can do with just the information "mons aren't spawning". We need more to really help you. The more specific the question, the faster a solution can be found.