Honestly, this was the first thought I had when I read the article. I worked in this space for several years and interacted with many doctors - just like in any other professional industry, some people have stellar reputations that precede them, while a few are infamous for their malpractice and unethical behavior. The perverse incentive arises when a hospital has a publicized malpractice lawsuit or criminal investigation - everyone who works at that for-profit medical institution has an incentive to protect its reputation (i.e. its profitability). This has allowed "angel of death" doctors/nurses to kill hundreds of people over the years, since there isn't much incentive to dig too deeply into "excess mortality" statistics (a famous example being Harold Shipman who could have easily been detected 2 years and over 100 victims earlier).

Covering up a case of medical malpractice by surreptitiously filling out discharge paperwork is certainly possible. A surprisingly large component of healthcare processes is to blindly trust that doctors are manually entering information truthfully and accurately. The fact that they couldn't locate her body for an entire year strongly suggests a criminal conspiracy to hide the body.