Hi @neyret,
Thanks for contacting us (though I’m sorry to hear you’ve experienced some difficulties).
Just to be sure I’m understanding correctly, you are using the include events in main blog loop setting here and your goal is simply to list any event categories? Or, alternatively, are you using some custom code to add events to the main loop?
Whichever approach you are using, the tribe_get_event_categories() function is likely to be your friend and can be used to fetch or display a list of event categories.