Vulnerable elderly woman left distressed after being sent a male carer in the night

My mum is 84 and has alzheimer's. She was recently in hospital due to 3 falls and an undiagnosed UTI. After one failed discharge we agreed a care package of 4 times a day care and one waking night carer (the waking night for three nights to settle her home and make sure she was safe at night)

After her discharge the evening carers came and all was well. I then get a telephone call at midnight from a male carer who had arrived to do the night shift and was telling me my mum was telling him to go. He wanted me to talk to her to persuade her to accept him. I said I wouldn't do that but asked to speak to her. She was guarded in her responses because he was there and I had to ask her yes and no questions: "Are you alright?" "No". Do you want me to tell him to leave?" "Yes".
He did leave without issue and the next day I contacted Adult Social Care and said it never occured to me that they would send a man, and how any strange man turning up in a woman's house in the middle of the night would be terrifying. How that wouldn't be obvious is beyond me. They have now arranged female waking care for the next few nights, but the experience has left her distressed, feeling unsafe and untrusting of the care in place.