They wont match up the address, theyre only looking at the money.

Yup, as long as the correct sales amount shows up on the return you won't have any issues.

I agree no tax implications, but I'd have the client contact the Title company.  It could be that the Deed and/or any other important legal document has an incorrect address also.  Correcting titles down the road is a hassle, do it now.

I'd contact the buyer and tell them to check with the escrow agent.  It's more their problem, and they are probably more likely not to accept false assurances.