Gotcha - shouldn’t be an issue with digging to get to the good stuff. That’s more of a small parrot thing with like parakeets and cockatiels.
If he’s eating some I’d just keep an eye on him. Fresh stuff you don’t want to sit for very long, but seeds and pellets can stay in a dish practically indefinitely until they’re eaten.
If he’s not eating at all, or less than normal, vet ASAP. Parrots are REALLY good at hiding symptoms, so any sickness that’s bad enough to make a noticeable change in their behavior means it’s already gotten pretty bad.
For food, just make sure he’s got a good mix - fruits, veggies, nuts, pellets… I’ve never had a macaw, so I’d look up any diet weirdness for them specifically, but in general, variety is good.
In a work environment, best response is to ask things like “why?” “What do you mean?” Etc and let them either dig a hole that you can bring to HR; or come to the realization that their derogatory mindset actually feels really dirty when they spell it out, and drop it on their own.