I don't think number 1 is a horses hoof (fomes fomentarius pls excuse spelling), I can't tell what tree it is on in your pictures but it looks a lot more like a Birch polypore (Piptoporus betulinus), commonly known as birch bracket, or the razor strop fungi, in the image showing the broken away area it is the fluffy material in the top section that can be made into great tinder, you can just dry it right out and then rough it up before use to increase surface area and can be used with flint and steel, you can char it like char cloth making this easier, boil it up and make amadou etc
here is horses hoof i was recently picking, both are polypores but the fomes is proper rock hard to get through the 'shell' and really looks like a hoof as it is always more tall than protruding from the tree, both make good tinder
Whoever told you it was Horse Hoof fungus is mistaken.
It's common Ganoderma, often called Artist's Conk, as someone mentioned earlier.
And yes, you can extract amadou from it (I have). You won't get as much as from Horse Hoof but it is still there just a much thinner layer. Cut down into and you're after the tobacco coloured velvety layer.
Personally I've always thought amadou was more trouble than it's worth. Never could understand the bushcrafter's fixation with it. Char cloth is much easier to make and more reliable. Ho hum.