Yikes, what a stressful situation.

If it were me, I would accept their current offer (9000 less than x) - since it will not put you in financial ruin, etc. It sounds like it will be worth it for your happiness and peace of mind which is worth so much more than that.

However, I also have to say that I don't like the sound of these buyers. I really really hope it works out, but I think that even if you take their current offer and come to an agreement with them, you should prepare yourself for the possibility that somewhere down the line the deal could fall apart anyway.

Good luck. Trust in yourself that you will make the right decisions.