Flew with five passengers and had 4 bags delayed for about three days. I did a lot of shopping in the interim, but British Airways only agreed to refund me 1500 dollars. They said that is their cap. Wouldnt it make sense that the cap applies to one passenger, and it should be raised when there are more passengers?
You should be entitled to that amount on a per person basis not on a per ticket.
You should submit separate claims per each passenger and different receipts [or highlight items per passenger].
Not 100% on this, but seems so.