Their documentation says you can augment the tincan.xml file in the root like so :
<launch lang="und">http://my.lms.com/TCActivityProvider/story.html
?endpoint=http%3A%2F%2Fmy.lms.com%2Flrs%2Fendpoint%2F
&auth=OjFjMGY4NTYxNzUwOGI4YWY0NjFkNzU5MWUxMzE1ZGQ1
&actor=%7B%22name%22%3A%20%5B%22First%20Last%22%5D%2C%20%22mbox%22%3A%20%5B%22mailto%3Afirstlast%40mycompany.com%22%5D%7D
&activity_id=61XkSYC1ht2_course_id
®istration=760e3480-ba55-4991-94b0-01820dbd23a2
</launch>
And now the endpoint will go to your specified url. But no matter what I do, the URL never changes, and all the JSON statements are sent to the root of where story.html is located.
When you set an endpoint in Articulate tincan storyline, it automatically appends /statement/ the the endpoint as a result the url for the LRS endpoint is not recognized. You need to create a rewrite rule and direct the json by Articulate to the appropriate handle.