Hello @madsrh,
If you need the event website URL, already nicely formed as a valid piece of HTML, you can indeed use tribe_get_event_website_link(). If you want the “raw” URL itself, you can alternatively do something like:
echo tribe_get_event_meta( get_the_ID(), '_EventURL', true );
It’s sounding rather like you’ve tried both of these without success, so what we’d need to know is a little more of the context in which you are using them. Can you share your actual code (please don’t post it directly in the forum, though – instead post it to a service like Pastebin or Gist and share the link here) and describe where it lives/at what point in the request it runs, and how/if you are deriving the post ID for the event?
Thanks!