Hi Amanda,
Great to hear you’re thinking of trying our PRO.
You’re right that there are a few difficulties in getting Headway and The Events Calendar to mesh, but potentially this would indeed offer you a way forward (and we’d love to hear the outcome ๐ ).
That said, we don’t offer trial copies but generally we’re happy to offer a refund if it turns out you can’t make use of one of our plugins (though I can’t guarantee anything, as really each refund request is assessed on a case-by-case basis).
Does that answer your question?