How very sad for your nephew and your family.
From what you describe, this matter should be investigated by an attorney who handles personal injury cases.
There are state and municipal requirements for apartment pools.
Photographs of the area should be taken as quickly as possible so that eveidence can be preserved before any remedial action is taken.
There may be possible defendants who can be held responsible in addition to the apartment complex.
For example, if there was a pool...
You need to talk to an attorney as soon as possible.
There is a statute of limitations in New York and from the facts stated, any action that could have been taken may have passed. What was the date of the last treatment by the Doctor who prescribed the oxycodone?
What a sad situation for you and your Family.
The details you provided are sketchy and I would want to know more about what occurred.
However there may be a case of negligent hiring of the Nurse by the Nursing Home.
You should pursue this matter with an attorney.
What was date(s) of the 2 MRI's you refer to?
Texas has a two yeat Statute of Limitations which has been strictly interpreted.
My opinion is that you will have a difficult time overcoming the two year restriction if the MRI'S were more than two years ago, particularly in light of your profession as a nurse.
Suggest you contact an Attorney who specializes in Nursing Home Litigation.
There are specialists in your area that belong to the Nursing Home Litigation Section of the AAJ --American Association for Justice.
It is difficult to fully understand your question, however, I suggrest you may want to contact DADS (Texas State agency) that deals with these issues.
You may want to contact the Ombudsman (if there is one for this facility).
Also, you may want to file a complaint with the Texas Nursing Board (if she is an RN or an LVN)