Agreed, the first is American Bank Note, #184, I'm pretty sure. The paper look is distinctive in this scan. The secret mark is there, to me.
The other American is #207. Here's a corner scan:

the heavy shading around the portrait oval is thinner but you can still see a trace of crosshatching below it. This one has a clear dash cut under the ribbon below "TS". This is not always as clear as this. The first thing mentioned is the key.
EDIT: Could we possible see the second stamp with less flash?