Someone in another thread talked about how their dog had anxiety in the car and would poop, so before they went for a car ride they would touch an ice cube to the dog's pooper and the dog would then do the duty.
Well, I thought this was interesting, so when I know about when Hailey is going to go (for me it's about every 5 hours), I tried going outside to a specific poop spot and touched the ice cube to her behind. I think that it helped her induce pooping, but it also had to be around the time she normally would poo.
Maybe you could try this method if your dog seems too distracted outside?