Well, I think I solved the problem…
In my sidebar, above the Types custom fields, I have a shortcode that pulls in three featured images from a particular custom post type. Turns out I needed to add wp_reset_postdata(); to the end of that function, then move the sidebar query to directly above the Types custom fields. New code looks like this:
<hr> <a class="more" href="#">View More Impact Stories</a> <hr> <div class="featured-strip"> [sidebar-posts-featured-img-caption type="impact-story" qty="3"] </div> <?php // display custom fields global $wp_query; $postid = $wp_query->post->ID; ?> <!--[wpv-post-id]--> [wpv-if donate_text="wpcf-donate-text" evaluate="!empty($donate_text)"]<strong> [types field="donate-text" class="" style=""][/types] [/wpv-if] [wpv-if donate_url="wpcf-donate-button-url" evaluate="!empty($donate_url)"] <a href='[types field="donate-button-url" raw="true"][/types]'>[types field="donate-button-title" class="" style=""][/types]</a> [/wpv-if] <hr>
Hope this helps someone.