What you want to do should be safe enough.
Have you considered dividing up the pastures to rotate them?
Can you change things up in the pasture? I move barrels around and change where the feed dishes go. I use old sheets and scraps of fabric to provide shelter and make it harder for air predators to get my animals. I move those around too. Chickens like variety and routine, but are not fans of major change.
I have a small orchard. The free ranging guys jump up or climb up or fly up to get the fruit from the trees. They also eat what's on the ground. No problems with the apple, pear, or peach innards. The girls in open fenced pastures get the whole fruit tossed into them. Sometimes up to 3 dozen apples in a day, per flock. No problems.
With my senior flock, I take 40 gallon buckets of dirt (from the garden) and dump it in their run. They are very happy to redistribute the dirt for me. (This area will be my garden next year and the girls will move to a different pasture in a week or so.)
I might add some mulch.
From the time of having baby baby chicks, I have pine shavings/poop. It was bagged and sat in the hot sun/direct sunlight for months. Then I dump it in a 40 gallon bucket, add dirt, and let it sit for a few more months. Then I dump it all in the open fenced pasture for the girls. (And no, the pine shavings don't break down quickly at all.)
I also keep a few 40 gallon buckets here and there. Besides the main garden, there are smaller chicken gardens. The chickens (guys and gals) love to dig around in there and do dust baths. The free rangers have no problem redistributing the careful placed mulch in landscaping beds and under trees. I don't worry about it.
Just my preference - I don't give the chickens access to freshly dumped bagged mulch or dirt. Once the stuff has a chance to gas off, I let them access it. I hope to be able to move to buying mulch & dirt bulk instead of bagged.
I've never done deep liter method in the pastures (open or fenced), but I definitely don't go and pick up chicken, duck, or turkey poop! Dog poop - yes - that does get picked up. Bear poop - depends on where it is. Cow poop - nope, not happening. Deer poop - nope. Rabbit poop - nope. Other bird poop - nope.
I use sand in all of the coops/animal houses. Works great. And the animals do dig around in that.