Dreadful party experience

We booked this company for our daughter's 6th birthday. We went for their Design your Own package- choosing the Gold option which should have bought us nail art, hair flowers, a chocolate fountain and a red carpet, amongst other things. On the day of the party the girls arrived late and were still setting up when guests arrived. They barely spoke to us and seemed throughout to have no idea of timings or how to manage a party. The nail art didn't happen- the girls said they had been told not to do it if they didn't have time. They clearly decided they didn't. The hair flowers consisted of one plastic flower gripped into each child's hair and looked naff. The guests were rushed through their food leaving a huge amount of waste and spent an inordinate amount of time queuing for things. I had paid extra for party bags and had a long list of what would be in them presented to me. I was told that the bags would be pink organza. They were pink plastic and contained around two items each, some of which were broken. I had to add to them during the party as I was embarrassed to hand them out. The red carpet and the chocolate fountain didn't happen.
I am currently pursuing legal action to get a refund and have been appalled at the attitude of the owner of this company. She has acknowledged, in writing, that the party wasn't up to standard but hasn't made any reasonable offer for a refund. I should add that this party cost £350. A refund of £80 was offered which simply doesn't come close to representing the amount of party that was missing. A dreadful experience made worse because it was a child's 6th birthday. Long awaited and much anticipated. We are not alone in our disappointment. I have since found several other 'victims' of this company.