You're not being nosey, no apology needed. No I don't work for any of the manufacturers, as I think that would be a huge conflict of interest for me and my hubby. He does work for one. Before that we worked together at one of the biggest lfs's in the country. I work independently these days.
As for the food, I would try something different. Stay away from wardley's tropical flakes, they're garbage compared to most of the others (as far as contents and manufacturing process goes). Aqueon is a good flake food, I use it now for many of my fish and they do very well on it.
Another food you could try would be Spectrum pellet food. Its a little more expensive, but the nutritional value is much higher than standard flakes. I am also wondering if there is a change in the problem when the fish eat sinking food vs feeding at the surface on floating flakes? If you get the new flake food and the problem is still there, try soaking some of the flakes in a cup of tank water until they all sink, then pour it into the tank so they don't feed at the surface... see if there are any changes in their behavior afterwards.
I am still thinking that the new food will likely solve the problem. Old fish food can do some very harmful things to the fish. Add some frozen brine shrimp to the list of foods, too. If you can get them to eat brine you can soak it in vitamins for them before feeding it to the fish. If their problem is nutritional based that would help to resolve it. If you have a way to feed live adult brine to your fish, even better... soak the live brine in the vitamins first. This procedure is called gut loading and is very effective for getting the right things into fussy fish.
Let me know what happens when you get the new food. The best we can really do is wait and see until then.