They are doing just fine in terms of food. Don't forget how hot it's been outside, food will go bad really fast in this weather and fresher/moister is better in terms of hydrating the falcons.
Once the kids can thermoregulate, it's not unusual to see both parents hunting for fresh food. This also serves as an early lesson to baby so he can see how food is prepared. Few more weeks he'll have to learn to figure it out on his own.
I know about all of what you said but I was wondering if DC was providing much food for the baby. I was surprised, as others were, when B prepped the food in the box. I don't remember seeing M/K or B/A prepping prey in the box before but I could have seen and forgotten it. It just looked like B killed the bird then brought it to the box to clean (so as not to be away from the eyas too long) after there was no fresh food delivered in early AM the 2 days before. Is this behavior something that you've seen at your sites? Good to see DC bring food in this afternoon though!
We also have a very limited view. When Carol tweeted (11:20) that B brought leftovers to the NB she was actually seeing Dot bringing in lunch. Beauty may be getting the food from Dot right out of our view. I think the changes in habits have more to do with human activity around the territory than anything to do with either mate. No typical workday activity today & nestbox activity is more what we're accustomed to.
Beauty likes a neat nest box. Yet I don't think a single meal at Quest & Kendal's was brought in prepped. That box was tail deep in feathers in no time. And Carly is right-some things need to be taught, even if you don't prepare every meal that way.