Second everybody: that is one seriously flaky company. I wouldn’t trust them even to pay your salary.
Was any of that even legal where you are? I’m pretty confident that in the U.K. asking someone at a job interview to state where they were born would count as straight-up racial discrimination (whether they gave you the job or not). And surely a signed statement saying that you won’t hold the company responsible if you get hurt on their premises isn’t worth the paper it’s written on: if a chunk of ceiling falls off and hits you on the head, let alone if they require their employees to engage in some dangerous working practice, you can still sue.