Google has added to their event markup documentation the ability for publishers to submit a reevaluation request if your site was banned from using event markup in the past. Aaron Bradley spotted this and posted about it on Google+.
He wrote "publishers can now request (re)evaluation from Google if event rich results aren't displaying a ticket purchase option." This change happened on August 6, 2018. The form should be used to let Google know that you want to be included in ticketing references in events on Google Search. The first steps you should take, Google said are:
1. Make sure that your structured data includes the offers.url field and that your URL meets the URL requirements for offers.url per events on Search guidelines: https://developers.google.com/search/docs/data-types/event
2. Tested the structured offers data using our testing tool: https://search.google.com/structured-data/testing-tool
3. Ask Google to recrawl your site: https://support.google.com/webmasters/answer/6065812
Here is a screen shot of the form:
I hope you never need to use it but it is there if you need it.
Forum discussion at Google+.
