Calendar shortcodes w/ category don’t display events when using DIVI theme

Hello,
We are using the WP FullCalendar plugin with Event Manager Pro and having some problems, we are using the DIVI theme and when we try and use the calendar with the category shortcodes, no events are displayed on the calendar. If we switch to a standard theme it works correctly. I have disabled all plugins and it makes no difference, the only thing that enables the events on the calendar again is changing to default theme. I have put in a support ticket to the makers of DIVI and they checked thoroughly and can’t isolate the problem. They asked me to: “contact the plugin developers and ask them how the posts are inserted in the calendar, it seems like this is the problem” Can you shed some light, maybe provide some help in solving this problem? I appreciate your time & assistance with this matter!