Mom is mad at me

My mom, step dad, and step brother are supposed to be coming down for my sister's wedding next week but she's upset with the sleeping arrangements. We have a 4 bedroom house. My 15 year old has his own room, my 10 year old daughter and 8 year old step daughter share a room because they just aren't ready to separate and then there's me and my husband's room and my our guest room. The guest room has one full size bed so I told my parents they can have bedroom and my step brother sleep in the living room or vice versa. They don't like that. They said that my step brother should room with my son and it's rude to make family sleep on a pull out. My son doesn't want people rooming with him. He's not comfortable with that. My mom said she feels like I just allow him to have his way all the time. Examples she's given are that he does not like being touched so he does not hug my mom or other family members. She finds that rude. I don't force him to hug anyone he doesn't want to. Also whenever we come to see the family we stay in a hotel because he's uncomfortable sleeping with other people and will not sleep if he's sharing a room. He has been through a few things so he does not like sharing a room with people. Especially men and my step brother isn't someone we grew up with. My mom has only been with my step dad 4 years and we've only met my step brother a total of 3x in those 4 years so we don't really know him. My mom thinks they should share a room. My mom knows why he doesn't like to be touched. Why he's uncomfortable sharing a room, especially with men but she takes offense to it and that I'm raising a generation of snowflakes by letting him have his way. I'm just trying to keep him from getting uncomfortable and trying to respect his boundaries.