The waivers depend. If everything was solid and by the book, the waivers may hold a bit. If you sign a waiver, and the company or person providing said waivered service acted in a knowingly negligent manner, the waiver is on much shakier ground because what you actually signed for was not in fact that which was delivered.
In my line of reasoning anyway.
Signed a waiver to board an experimental sub to do an inherently dangerous thing is one thing... Signing that same waiver to board an experimental sub that was built with parts not certified for the inherently dangerous thing is something else. One would have a reasonable expectation, in absolving the company of responsibility should something go wrong, that the company is providing an experimental vehicle that is as safe as possible... That was not the case.