If the so called buyer has a home to sell..............she isn't a buyer!!!!!!!!!
You need someone to be ready, willing and able...............having a home to sell first doesn't make her ready or able!
Get your home listed, and let an able buyer come along who can perform now, not in the future!
As I noted in your previous question, I do take a named exclusion, but only for 7-10 days. I would never list a home with an exclusion that lasts indefinitely. It isn't fair to the buyers who will be brought in with agents........plus....agents won't want to show your home, as exclusions must be duly noted on the listing (in my area, anyway).
As noted below, your question was duplicated on our site. You can see the answers to that post at the link below.