As uncomfortable as it is, you simply must take photos of the bedsore or other signs of elder abuse, neglect, and malpractice.
No one wants to roll their grandmother or mother over and take such photos, but it is simply needed.
As they say, a "picture is worth a thousand words."
Pressure wounds, bed sores, heel sores, blisters, redness, swelling, drainage and odor are all signs that a loved one is being mistreated.
Worse yet, sacral or tailbone sores, are often infected when one is laying in their own waste. Fecal matter is the worst offender.
This often leads to sepsis. When one becomes septic, the blood is actually poisoned.
Early detection prevents worsening. Early documentation prevents dishonesty.