Good evening Ian and welcome to the Events Calendar Support forum!
Thank you for reaching out to us.
We are sorry to hear about the issue you are experiencing with ticket emailing options.
I would love to help you with this topic.
Try temporarily reverting back to a default WordPress theme such as twenty-sixteen to see if the issue persists.
If it does, you could apply the following snippet in the functions.php file of your theme (without the PHP tag at the top): https://gist.github.com/jesseeproductions/9ff8863230e5a05b9303#file-tribe-tickets-plus-prevent-emails-php
Let me know how that goes.
Best regards,
Geoff B.