Something else, you mentioned that the pee-pads have a "fresh-scent"...this is another thing that you must avoid all the time. You can no-longer buy ANYTHING that has any type of added "scents". Nothing. No candles, no room sprays, no incense, no cleaners, no oil diffusers, etc. Same thing with anything that contains Teflon, like your pots and pans, if you have pots and pans that are the black, non-stick Teflon coated kind, you can no longer use them at all, you have to get rid of them and buy either ceramic non-stick ones, or use cast-iron ones. Some space heaters, blow-dryers, air purifiers, etc. also contain Teflon or a coating inside that emits the same fumes that the non-stick pans do, and it instantly kills birds...and I mean instantly. You can't smell the fumes that the non-stick pots and pans release, but I believe it's when any pot or pan, including non-stick baking pans, hit 400 degrees F or hotter, they release lethal fumes that instantly kill birds, and there's nothing you can do when it happens.
As far as anything that is "scented", birds are extremely sensitive to most-all scents and can become extremely sick and die quickly just from a scented candle burning or you using a scented cleaner. So even though you can't use ANY type of pee-pad in the bottom of their cages, regardless of whether it's scented or not, the "Fresh Scent" is just a double-whammy. You have to start cleaning with either natural cleaners with no scent, like the ones that are clear and made from plant products, or just start using a mix of white vinegar and water to clean with. No carpet powders, no scented floor cleaners or all-purpose cleaners, etc.