Welcome to the forum. Tiki looks very cute!
I would be establishing a routine with Tiki. Paper changed daily in the morning, wipe over the tray. Wipe over any bars that might be dirty.
if you are having to open the cage doors to get his food & water pots it might be worth just moving the toy to clean it if you are able too. If Tiki is not too upset by the food and water change, it might be worth just removing the toy with the poop on and cleaning it. Just make slow, careful movements and use a reassuring voice while you are doing it.
If he does seem scared just stop and if he is too afraid and you don't think he is ready, then don't attempt it right now.
My personal routine with my birds is a paper food and water pots clean daily- water twice in hotter weather and I do a weekly clean where I wipe over perches. If your bird is pooping on his toys, try and find a better place to hang them, if they are underneath a perch (if he's just climbing on top of them, then there's little you can do).
Millet can go a bit dry. You can see the difference between fresh and old millet in pet stores. As millet is a treat, they don't need to have so much in there that it should go bad. I rarely give my guys millet and I usually give them one spray between 8 of them.
Veggies are much healthier for your bird to try.