Hi yes our emails sometimes does not works , we are checking that , judging from your explanation it seems like you are building some custom blocks there , you can add custom info text there .
In wplms we use woocommerce product for course purchase see : https://www.youtube.com/watch?v=gIxv_-15ro8
So the price of the woocommerce product shows for the course and you can set the price accordingly for the course .
you can use [course_button id="{course-id}"] in order to show the button there .
{course-id} to be replaced by the course id