It certainly looks like where an abscess could have blown out. I'm not a vet though. But yes, it does look like it, especially if that hole is deep.
If I were you, I would be thrilled about finding the hole(s), because that is a much better diagnosis than founder.
I have seen them blow out at both the coronet band and the back of the frog. I don't see why it couldn't come out at the bars either though.
So hopefully it's that, especially if the horse is suddenly better.