Ok, this is getting out of hand. We have numerous ways of saying ‘exactly’, including ‘exactly’. We also use ‘that’s the thing, isn’t it’ in the way you describe for the US. I think this whole premise if false.
And ‘Innit’ is highly region and class specific. If someone says ‘innit’ and they aren’t from Essex or a working class neighbourhood of London, they are taking the piss.
While to the American ear “kip” seems so odd, but it’s just a word to Brits. Not really slangy, just less familiar to us. But “crash” has it’s problems. A wash?