Oh, I know for a fact it wasn't the eels. And yes, they do stay in the cave all day, and roam the tank at night. And if the eels wanted a snack, there's 3 much smaller tiger barbs they would have no problem getting if they wanted. But it was one of the big ones, an inch and a half. When I first looked into the tank, the eels were in the cave on the left side of the tank. 5 minutes later, looked at the tank and the tiger barb was in a helicopter spin, with 4 other large barbs by him, and the eels were in the cave. So I know it wasn't them.
Not sure what kind of eels you have had exxperience with, but the fire eels aren't true eels, are very calm, and will feed out of my fingers. And don't appear to have any teeth either, as it's a fish and not a true eel. If it was the eels, I would have seen them outside the cave, which they were not. So my best guess is the bully albino tiger barb in there, almost 2 inches in size.
So I'm just going to keep a closer eye on things while I'm home. Fish are so much fun to watch, and see how they interact with other fish. it's so enjoyable, even you go through loosing a fish or 2. It's totally normal in the wild. but sometimes you still get so attached and don't want anything bad to happen to them.