Amir, I sympathize for your loss.
I visit the Govt, health facilities a lot due to age and lifestyle related issues.
Visit the ACC, as soon as you enter the door, you will see the helpdesk. Tell them your complain and they may ask you to fill out a form or meet the Administrator and you can take it from there.
My Dr. are always asking if I am ok with the treatment and also receive SMS from MOPH for a feedback. I have also received calls asking about my last visit and the way dr. and staff behaved and overall experience with HMC and PHCC.
Sure your case will be looked into since it is a loss of life.
I have very good experience with HMC and PHCC and their affiliates and rare forgettable bad experiences.