Your pictures of the yellowish droppings look like they are probably normal cecal droppings. Those happen several times a day. https://www.communitychickens.com/how-your-chickens-cecal-pouches-affect-its-droppings/ However I do see a lot of intestinal lining in your other pictures, so I would get a fecal test done to rule out any parasites. There is lining in the dropping you focused on, and in some of the others around it. When I see droppings like that in my flock it's time to worm, I have to treat regularly for roundworm. I would do the test, better safe than sorry.