Is it right for a newly hired live-in caregiver to demand that the family members do not visit or call so that he can train the elder person?

Divide and conquer. Yes, too many involved in decisions can just delay the crucial and timely decision to fire this caregiver. He threatened to quit if you don't comply? Ok then! The trial period just did not workout-there are other caregivers.
The caregiver has already divided the family.
Why would your other siblings want your brother out?
Who is the one spokesperson, the one in charge? Who hired the caregiver?

Josephine, I think you would all be more comfortable if your dad was in a professionally run facility.

Sorry to be so wordy -- maybe DEMAND was too strong a word. He said I will leave if you do not let me do my job. I say clarify expectations and if he doesn't like them he should leave. My siblings think he is a godsend and will do anything to keep him. Having too many siblings involved in care is not always good. Especially when the most vocal decision makers see my father the least.

Geez! For some reason this one pushed my buttons! Sorry for yet another opinion from me. Okay - say one of your siblings made these say demands - wanted to seperate and isolate your dad from the rest of your family. You'd wouldn't allow it and would be highly suspicious, right? So why would you accept it from a stranger?

Thank you. That is my feeling/. Some of my siblings are telling me that I am not holding my father's best interests at heart because I am "denying" the level of his impairment and that he needs this new caregiver to take total control of his life for his safety. We've known the caregiver for two weeks. He comes highly recommended but before he moved in he changed the entire house -- threw out or relocated a lot of my father's possessions (in the name of "dust") and didn't ask. My father now thinks he is living in someone else's house and has had panic attacks. He calls repeatedly to me and my siblings Some of my brothers (I have six) think that his calls are a sign that he is losing it more and more and they don't want to be bothered with the burden of answering them. I think they are just a natural reaction to a very stressful change and that the more we can ease his anxiety by being there the better. I see my father four out of six days a week and feel that I have a better sense of his range of behavior than some of them do.. To complicate matters, one of my brothers had been staying overnight at my dad's house before the caregiver arrived to help him if he needed it and because my dad's house was an easier commute to his job. In the process he used to spend time at night watching tv with my father. Now the caregiver and my siblings want this other brother out so that "the caregiver can do his job and my father can not be confused by having a son in the house. I think they are going to make my father worse and take away any of his spirit and personality just so that they do not have to be bothered with his incessant phone calls.
We've known the caregiver for two weeks. I think it is crazy to give him total control.

I'm still bugged by this post so here's a few more thoughts: I don't like the verbage in your question. Are these words, "demand" and "train" really accurate? I would be wary of any employee who makes "demands". As for "train" - your dad is a human being not a puppy! As for depending only on him - what happens on sick days or he goes on a vacation - your father would be completely devastated if he felt this guy is the only one he can count on. Lastly, this kind of control is the first step towards financial fraud. I suggest rethinking this caregiver.

Re-read your post. The caregiver WANTS your brother out?
Just fire (delete expletive) the caregiver, report to the agency.
This is way more dangerous than you may know.

The caregiver is controlling. I was never for the concept of no visits until your loved one gets acclimated or 'trained'!
The caregiver can work around family visits.
Even though this is a red flag, (attempting to isolate the patient) maybe the caregiver can be trained. The caregiver should not be making demands.

While I see some logic in this - I am also seeing a big, red flag. Is this a demand or a request? I think I would also factor in this guys level of experience. I'm assuming you did reference checks and a criminal background check, yes? Personally, I don't think I'd go for it - something about it just strikes me as off and a little too militant. If if were me and I was gonna give it a shot, I would think about installing nanny cams or even the in-home surveillance you can get through cable companies and not make it a secret. The guy shouldn't have an issue with you observing from afar, right? If he has nothing to hide. Also I think I would want to tweek the arrangment to allow for some regular visits and phone calls - it wouldn't have to be daily but at least somewhat regularly, at least in the start.

Absolutely it's not right! It looks like your post got cut off mid-sentence so there may be more, but I can't see any way this is right. Especially in the beginning it is critical that the family be able to keep a close on eye on whether this caregiver is doing their job properly and is a good fit. If you go along with this guy's plan, you will have no way to know if your father is in trouble, if the caregiver is lazy, or if he is abusive.