If your daughter signed a contract back in December, along with the other house sharers, I don't see that they will have much of a choice. If contracts are signed, they don't all get to decide, that one person can be removed from the house. Your daughter's contract is with the landlord, not the people she's sharing with.
If the other people in the house share don't want your daughter living there, then they all will need to cover your daughter's portion of the rent. To leave, your daughter will have to approach the landlord, to see if they will release her from the contract. It's possible the landlord will agree, if a penalty is paid (it's a possibility, as it's breaking a contract) and if the others agree to covering your daughter's portion of the rent.
Your husband needs to look at the contract signed and speak to the landlord. Unfortunately, your daughter may not have much choice about going into Halls, because it's late in the day to find somewhere else suitable for the new term year. I suggest speaking to someone at the University who deals with students with additional needs.
I feel for you OP and your daughter. I agree with someone else, it's likely not 'one thing' or 'one incident', it's probably a lot of ND traits together. I work in a school, so see ND children, and the struggles they have socially, and it's hard for them.