I, too, could potty-train a macaw but it was not so elaborate as this. When outside her cage, there was a designated poop perch and if she was out longer than 20 minutes, I would take her to the perch and let her drop cargo. She knew the drill. It was very effective.
Even on road trips Max would opt for pooping in a toilet if it was available. More than once I endured a confused clerk as I carried my bird to the rest room.
Otherwise she would go to her cage to do her business.
Birdie too once he’d joined us (he actually decided to potty train watching Max get praised,as he was an older bird when I got him).
Made long road trips a blast. Max would camp out by my left ear and Birdie would snuggle on the right under my chin.