Hi,
Thanks for using our plugins. I can try to help out here, but I am limited in supporting customizations.
Per our terms and conditions we support features of the plugins and although we try to help get you started on customizations for the most part you are going to have to take it on to complete.
Since we do not have tabs by default I am not sure the best way to move the ticket for to get it there. That is not something we can support as it is unknown coding to us.
We do have this guide to moving the Event Tickets Plus ticket form:
https://theeventscalendar.com/knowledgebase/moving-the-ticket-form/
You could use that to move the form to a hook you add yourself.
Does that work?