How do you go about getting the people to accept them, and can you get them to join your squad to go to Pripyat? Any help would be greatly appriciated.

try talking to the leaders of Duty and Freedom at Yanov.
one of them will accept them probably... With me Freedom didn't, might be because I have a better relation with Duty :P
If you get one of the leaders to accept them, find the (ex)monolith leader at yanov and talk to him about your squad to pripyat, he joined me.
Good luck with it! hope this helps!

Have teried again and again to get freedom or duty to accept the monolith soldiers. Is there somthing that I have to do or get to give to freedom or duty to get them to accept the monolith soldiers? Any help would be greatly appriciated.

you have to do the quest from owl (delivering 3 veles-detectors to the scientists)
after that you get a scientific detector from beard
with that detector you can see and activate a time bubble anomalie at the cooling tower
you will find something in there that will help you get a good relation to one of the factions (depends on who you give it)