I posted at 12:15 before I saw this response, OP, and rage was also a part of my dad's illness. He was immensely frustrated with his inability to control the situation and lashed out at everyone who came to help. In the end, he was even telling anyone who would listen (like church members who called the hospital) that we wanted to give him the pain medication to kill him off.
I know some of it was just old-age dementia, some was that the cancer had reached his brain. A good part of it was that pain, fear and exhaustion had just completely wiped out his coping skills.
Keep hiring help and asking your dad what you can do from afar. Just be aware that trust is tenuous and appreciation may not be coming
Sometime that night my stepmother came in, saw that the table had been cleared up, and flew into a rage. She was convinced that I threw stuff out (I didn't), looked through her papers (I didn't) and invaded her territory (I guess I did--although it is my dad's home too). She evidently was up all night screaming at my father, and told him to tell me to leave and that I had had done something unforgiveable. She also started screaming at him for being unreliable--he was supposed to take care of her and now he's the one needing help; she threatened divorce, not to do chemo, to move out, etc.