Renting together when one has bad credit

You're right - the answer IS no. His poor credit is a red flag to potential landlords that even though he makes enough money to help pay the rent he may not actually do it. The only real way around your situation is to have a guarantor with excellent credit AND income co-sign.

Another workaround is to offer a few months rent in escrow or pre-paid. Perhaps even the whole lease term, if your savings are that substantial and not needed for other purposes.

But this is a problem that really only goes away either with a separation of finances, or with improving his credit score.

You can use services like Insurent which will act as a guarantor for a fee.

Try offering 3 month deposit or 6 months rent advance but rent in both your names.

What neighborhood is this in?
What kind of landlord and apartment building? Is this a single brownstone owner, a large multi-building landlord, a Trump building, etc?
Are you dealing direct with the landlord or landlord rep, or working with a broker? How have the discussions been? Do they know there will be 2 tenants?
How old are you both? Have you lived together before (whether on the lease or not?)
Are you moving from a referenceable landlord's building?
How long have you both been employed? Is it in a respectable field, or are you in a field where you give advice to random strangers without asking sufficient questions in order to be able to give that advice?
How much have you saved up relative to the annual rent?
How close are you to a commitment between the two of you that is more than boyfriend and girlfriend? What would be the impact on you if he skipped out?
Do you have a guarantor? Who is that guarantor? Where is that guarantor?
Why didn't he pay his credit card debt? Are you concerned about that? Is that being rectified? Was it one of the good banks or one of the bad banks?