Hhmmm... interesting... It's getting late so I'm not going to go off grabbing links but I can provide personal first hand experience in a relatively short manner.
I'm very familiar with self-injury (several methods from "high to low"). I tend to believe that while the risk of suicide may be greater than the average "healthy" population the overall risk is relatively lower than one might expect. It is usually an attempt to soothe an absence of or diminished ability to feel and of course a large dose of anxiety. I'll have to look into the stats and studies more tomorrow.
I am sorry to hear about your daughter's sensory challenges. My son's sensory integration issues are no where near your daughters but I am familiar with the spectrum. We are very lucky that he is better able to cope as he has gotten older. You'd never know he has any challenges whatsoever until you try to cook a meal for him that he'd eat/enjoy, buy clothing, have him write something down (legibly) or transcribe notes from a chalk board to paper.
I think it is possible he was either misdiagnosed when he was younger since childhood onset of schizophrenia is so very rare and that he presented with other rare traits... however I think it may be more likely as he got older that his Aspergers posed more problems than he was able to manage which in turn increased the likelihood of any number of personality disorders becoming extremely problematic.
JMO... hoping we will eventually learn the full extent and factual diagnosis.