Hidden testimonials category

I was building a one-page site based on My Simone when I stumbled upon a problem with the testimonials section. You hide the posts for each testimonial by hiding the testimonials category with the function exclude_testimonials so they do not appear in the index of the site. The problem is that they do not appear in the WP dashboard too so I cannot edit them from there and change the text the way I want.
I found that I’m able to see them in the WP dashboard when I comment the function which hides them, but this is inconvenient in my opinion. Isn’t there other way around this issue?