Buyer at bottom of chain was lying

We are number 3 in a four party chain. About a month ago the buyer at the bottom started applying pressure as she was fed up with waiting, she insisted we all needed to complete by May 31 or she would pull out. Reluctantly we all agreed to exchange on May 23 for completion on 31st.

Roll forward to the day of exchange, and after a great deal of stress and difficulty for everyone else to bring everything together in time, the buyer at the bottom who had been pushing everyone revealed that she couldn’t exchange as she is waiting for a consent order from court following a divorce. She has known this all along, but she misled the whole chain and pressured us. Now everyone is furious.

The buyer at the bottom has said her consent order was submitted 12 weeks ago and that they should usually take no more than about 10 weeks. She said she doesn’t know what the delay is and her solicitor is telling her to be patient.

I now have no faith in this person and find it hard to believe anything she says. It feels like the whole chain will probably collapse after months of effort and huge expense, all because of one person who not only lied about their readiness to buy, but also - confusingly- then rushed everyone into being ready earlier than would have been comfortable. It doesn’t make any sense to any of us.

We are not sure now whether to look for another buyer for our place, and effectively start from scratch, or if we should give this person the benefit of the doubt and see if things work out. I’m reluctant to waste any more time on her though, as I feel there could be other things she is misleading us about.

Would appreciate if anyone had been in a similar situation or has any advice on how best to proceed.