Don't know if it would help, but there are really good but inexpensive ( $20 ) wifi cameras available now that you could use to monitor the food: www.wyzecam.com. They also record continually so you don't have to actually watch at all times to see what happens. I know you are trying to prevent one cat from eating the others food and just watching them wouldn't do that but maybe you can use a camera to see how well a possible solution works.
You could buy a cheap game camera which would allow you to see who is eating and when...The only door would be the bedroom door but I don't allow the cats access to the bedroom when I'm not at home. My mouse lives in the bedroom and while the cats pretty much ignore him, I like to be extra cautious. The litter box is in the bathroom and both cats need access to that.
Remotely opening a feeder via WI-Fi would work in theory but I'd still have no idea if Leroy is eating the food or if it's Emma. I think Leroy would need a sound cue to (eventually) make the connection between sound and food available
I'll look for a local handy man. I don't have any relatives or friends who have tools to turn a storage box into a feeder box.
