This is so sad.
I can relate with your family because we had same experience when my father in law was admitted just for liver biopsy on a week-end and he died the next day unexpectedly. My father in law was ambulatory and strong when he was admitted. He survived the open heart surgery in the same hospital 8yrs ago but did not survive the simple liver biopsy.
The hospital is responsible in making sure all healthcare personnel are competent and should not make excuses and justification to these incidences. It's one of the best hospitals, people seeking health services at SLMC should be safe. I understand that some patient who are admitted very sick dies but these victims are sick(healthy) individuals and are just victims of circumstances, it could have been prevented & patient should survive given the best attention and care. They should treat everyone who come through their door cautiously and anticipate the worse that could happen before we lose our loved ones.
My sympathy goes with the family, may you have strong faith with the Lord. God bless you all.