Four bridesmaids were booked into one hotel room with two beds

Four bridesmaids were booked into one hotel room with two beds.

My mother made the reservation and assumed the hotel would add two rollaways. The room allows one rollaway because of fire-code clearance.

Two bridesmaids are willing to share beds. The others expected separate sleeping space after paying their portion of the room.

The hotel block is full. One suite is available at the public rate, which is nearly double what everyone agreed to pay.

My mother says they will barely sleep and can treat it like a college weekend. They are adults arriving after flights, and wedding participation should not require nostalgic overcrowding.

My fiancé and I can cover the upgrade to the suite or book a nearby hotel and provide transportation. The suite is simpler and makes my mother's booking assumption our expense.

Would you pay for the suite, move part of the group or ask everyone what arrangement they will accept? When someone else coordinates wedding lodging, who owns the cost of an assumption that was never confirmed?