Disney showroomprivé reservation

Hello,

I made a reservation on the showroomprivé site for a one-night stay at Disney at the Sequoia + park access for 2 days on the 11th and 12th of November. When I went to print my voucher the day before departure, I realized there was a date error. The hotel confirmed that they are not expecting my family (two adults and two children). We had taken the cancellation option, so it makes sense that if we wanted to cancel this stay, we would have activated the insurance. Today, showroomprivé does not want to hear anything, and the insurance does not apply, which is understandable since the issue does not correspond to the insurance's terms.
I had sent documents proving that we had made all our arrangements with our employers and the children's school for our stay from the 11th to the 12th of November 2019, and in no way for another date since no other date suited us at the end of the year.
But showroomprivé is not listening to us and does not want to hear anything now that it’s paid.

The disappointment of our family, especially our children who were supposed to have a magical stay for their birthdays, is great. I saw on this site that others have experienced the same problem; what were the outcomes?

Thank you in advance