The AL my parents are in seems to be slipping - what else do I need to do?

My parents were in AL for 9 months. No complaints & loved the staff. But interactions with other residents were limited as many had cognitive deficits worse than my parents. So off to IL they went...BIG mistake! After 5 months, my 88-year-old mom had an exacerbation of a chronic condition & my 92-year-old dad couldn't take care of her. Back to the same AL. Staff excited to have them back 'cause they were well-liked. I had to add additional services for mom since her physical & mental abilities have declined.

Since then, parents have had nothing but problems, such as staff not showing up as scheduled to help her get ready for bed, not coming in a timely manner to help her to bathroom when she calls, not cleaning their apartment when scheduled, not doing their laundry, & not giving meds on time. Recently mom got no meds at all the whole day! I met with the director of nursing twice & left telephone messages that were not returned. I was told that these issues had been corrected, but as of 2 days ago my dad still has had to go looking for someone to help her. He's told they'll "be right there" but then never show up. It's seriously affecting his physical & mental health.

I've left messages for certain other staff members to contact me & they either did not get the message or just have not returned my calls.

I'm making an appointment to discuss with the newly-installed director. If no results, I'll go to their corporate leadership. I hate to do this, but I cannot have this - it's been going on for about 3 weeks. I sympathize with the staff since I also worked in healthcare & there are never enough staff. But I'm very frustrated & may lose my temper! I fear if that happens, my folks would be subject to retaliation.

For those out there with cooler heads, please recommendations how to express myself firmly, but not hysterically, in order to get these issues corrected. I'm bewildered at the sudden decline in quality of care.