Use custom field value for zotpress

Hey!
I have created a custom type called “Project”. This type “Project” has a custom field called “Project Collection” which holds the ID of a zotero collection.
I have created a project template called single-project.php. In this template, I take the value of the “Project Collection” field and store it in a variable called $zotcol. I am trying to use this variable with the zotpress shortcode to display my collection. I am trying to do this in the single-project.php file.
However, when I try to do this, the zotpress shortcode is interpreted as text and the zotpress shortcode is just being displayed on my website.
I am at a loss as to how to make this work.