If you look at the bottom image you can see the faint line of the die crack. The coin was listed/sold as having a colon.
I'm aware a variety is listed for the 1851 Farthing with a purported colon.
Looks like the beginnings of a die crack rather than a colon to me.
Could be they drilled a small hole in the die to limit the crack. It is a well known technique to drill a small hole at the end of a crack as it reduces the stress at the tip and so makes it less likely the crack will propagate further.