Just figured it out after some digging around in the other plugin’s code.
The custom post type created by other plugin was named “endo_wrc_cpt” instead of something logical like “random_content”
After finding this out, I simply went into the WTI settings and added “endo_wrc_cpt” to the “Post types to use”.
That solved it for me, and now everything is working exactly as intended. 🙂