i am with the other posters, if the financials do not pass , no reason to go to the next step. You are opening up a can of worms, cause it looks suspicious.
If i was selling i would want the same, financials pass, next step, if they dont pass, and it looks legit , time to find a better finanancialy qualified buyer, and if using a RE agent, i'd be asking a lot of questions of how the person was vetted finacially by the RE agent or are they just throwing people in , and not doing their job, in which cse the contract should be cancelled,since they are screwing ,you ,the seller and expecting to get paid if they luck out. It may be worse next time, a denied mortgage at -24 hours.