1 - so anyone with half a wit will object that you not knowing the law doesn't mean that there isn't a law (which, btw, would be better rendered as process), and they'd be right. But, here's the thing, the same applies to everything; just because no-one alive today understands the process that led to something doesn't mean there isn't a process.
2 - I say 'clearly' because I have no idea what the chance is. Neither does anyone else. In the ID slight of hand they give you examples like tossing coins and pretend you can extend this to unknown areas. You can't. You can't say anything meaningful about the probability of something until, and unless, you understand the processes around at the time of its occurance.
And there's a second problem here too. Let's suppose that we could find out the probability and it came out to 1x10-18. Gosh, we'd go, that's crazy unlikely, surely such a thing could never happen!
Is that right? Well, let's suppose your rock is 10cm x 10cm x 10 cm, that's 0.001m3. The Earth's crust is varies between 5 and 70 km thick; let's take the lower of those numbers. The Earth has a surface area of 5x108km2, so that's a volume of rock of
5x108km2x5km = 2.5x109km3 = 2.5x1018m3.
Which means there are 2.5x1021 pieces of rock of the size of your sample on earth; so if your rock formed by chance we should expect that there are 2500 pieces of rock of that configuration on earth. Not so unlikely that it exists now, is it?