Discrepancy in Background Check: Job Duties

I got an offer from a company after 6 interviews. And I just got a copy of my background check and it says complete- discrepancy. The dates are a match but the job descriptions duties aren't.

Long story short, My boss at my previous employer was a racist and gave me a ton of work over other employees. She was quite disorganized and handed me duties out of my job description which I included in my resume.

I reached out to her letting her know my new employer would be contacting her, attaching my resume. And she responded by saying I did not do many of the duties I have listed on my resume, which in fact I have.

I'm a little concerned, because of the discrepancy will I be disqualified from this position? What do I do ?

usa jobs
usa jobs resume
usa hotel jobs
usajobs
usa jobs federal government
usa job in ksa
usa jobs
usa jobs login
usa jobs gov
usajobs.gov
www.usajobs.gov
usajobs.com
usajobs
usajobs.gov official