Respondents in the case had retained Donald Samuel and Amanda Clark, two top criminal defense lawyers, in the civil case that was attempting to review the physical paper ballots in the county. The pair of attorneys were representing Fulton County Board of Registrations and Elections’ Teresa Crawford and Aaron Johnson, the two Democratic Members.
My guess is that the case is not defensible and they don't want to go down with a sinking ship, or quite probable imo they were concealing evidence or somehow obstructing the case and had to stand down rather like a judge recusing themselves.