As long as your brother has b2visa, he can visit you. You can invite him.
Getting a b2 visa is a different matter. It may be difficult like my colleague pointed out.
Consult with an immigration attorney.
I can't say about Atlanta GA. I usually attend my clients' interview here in Seattle, Washington. Interviewers here are reasonable enough to understand circumstances like you described. If the interviewer really believes the document is vital enough, he/she may request RFE and give you time to obtain another copy.
If you are still uncomfortable about the stain on the original document, perhaps hiring an immigration attorney to attend the interview with you might be another option. Many...