How to avoid duplicate post display with multiple query loops

Using Tenaz template in WordPress, it shows a list of “recent posts” in each post. The post itself is often duplicated in this list. On the front page, this also occurs with a query loop related to “trending.” As you can see, my featured image caption is also malfunctioning when the post appears twice. I was going to seek support from the featured image plugin when I realized support would say “get rid of the post showing up twice.”

This article captures my issue well, but I’m afraid to go into the code and not sure where I would put it. Is there a plugin for this problem? Seems like it would be quite common.

The page I need help with: [log in to see the link]