It seems like you’ve created a static page, placed 2 WPSP list shortcodes and then assign it as the Posts page on Settings>Reading?
If that’s the case then it makes sense why the shortcodes were not working.
Assigning a page as the Posts page on Settings>Reading turns a page into a default blog index page. This means, it will disregard all the contents of the page (including the shortcode) and place a Blog list in it.
Iām just letting you know for future reference how I worked around the issue.
Thank you for sharing. Glad you got it sorted. š