The Schindlers made those atatements, because that's what they believe. Lies, or "no comment" are not allowed.
They may very well have believed that or if they were under a huge amount of stress or not too bright they could have made statements that were not relevant to the question being asked but more about what they really or knew, which could have been that she would have wanted to live.
I don't believe in disregarding another's wishes. That said, there may be people who would disregard a person's wish to live as well. Which makes the acceptance of hearsay as evidence ridiculous.
We need to get back to the presumption of life and let those who want to die write it down. Have forms available at your local BMV just as the organ donor registration is.