Really sorry to hear about this, but I have a possible solution. I've got a joker expiring in November which I'm not going to be able to use. After a little behind the scenes discussion, I think I can use this on behalf of anyone in my travelling companions list, and under the circumstances I'd be happy to do that. And thereby to open up availability over the next few days so you can shift your booking.
This does depend on whether this is possible under BAEC rules, and I need to invoke @
corporate-wage-slave to ask how this might work.
If the principle works, we can move over to DMs to make the arrangements.