Not practicing law in your state though, so you need to consult a qualified lawyer in your jurisdiction to see what to do

If they want to bring on a new roommate, you screen them like anyone else and if they qualify, great- you can talk about amending the lease at that point, but that is only a courtesty. 

And THE most important thing is that you have to work with a Qualified Intermediary BEFORE you close on the property that you are selling.

A tenant doesn't qualify for a S8 voucher by making good financial and life decisions, so what quality of people do you think the system is dealing with?

In a tenant friendly state you have to.BTW, when you list, there's a fair housing law. you cannot deny a sec 8 if they qualify. your standards need to be the same for everyone

I do qualify for being a broker which comes with some additional education etc. 

Any recommendations for a qualified Intermediary?

The most likely options are exchanging:Life insurance for life insuranceLife insurance for endowmentLife insurance for non-qualified annuityPersonally, I would first determine what type of exchange you want to do. 

You do have to qualify and be accredited in most cases to join such clubs, but they do exist.

If the lender used your credit report as part of the decision, they should also include details about the credit reporting agency.It’s worth following up with the lender to formally request this denial letter and ensure they’re compliant.