Brown, the founder of both, is on trial in federal court on fraud charges.
Lab parent Richard Weiss, who has been part of a group working to clean up the school, suggested that a "rogue" member of the charter's board was trying to sabotage the process.
The majority of Lab staff and parents have been working to combat "cronyism and wasteful spending," Weiss said.
The school, Weiss and others reminded the SRC, is the only Philadelphia recipient of a 2013 National Blue Ribbon, given by the U.S. Department of Education.
The resolution to renew Planet Abacus, in Tacony, came before the SRC, but failed to pass. Commissioner Feather O. Houstoun said she was troubled by a lack of publicly available information on the school's website - an issue district officials have raised with the school.
Commissioners Sylvia Simms and Wendell Pritchett voted in favor of the Planet Abacus renewal; Houstoun voted no, and Joseph Dworetzky recused himself. Resolutions need three yes votes to pass, and the SRC is down one member.
Both schools' charters presumably will come before the SRC later.
The SRC also voted to allow People for People Charter School to add high school grades, but not expand past its enrollment cap.
The commission also heard from students who wanted more of a say on school lunches.
Nadia Watson, a sophomore at Kensington Business High, said lunches "are unappealing or look like something that you can't even explain." Watson, a member of the group Youth United for Change, asked for students to be included in taste tests as the district prepared to approve a contract with a food-services provider. Officials vowed to continue to work with students.
Parents and staff also reminded the SRC of the effect of the district's brutal budget. Many schools lack full-time counselors, nurses, supplies, and programs.
Counselor Ruth Garcia said she came to speak for children "who deserve more than they are getting." Hite told the SRC that there were now 220 counselors serving 212 schools. Some schools have more than one counselor, and 40 schools share counselors.
Parents from Cook-Wissahickon Elementary in Roxborough chided the SRC for allowing "split classes" - one classroom with two grades - to exist. "When you throw split grades at us and shortchange us on resources," parent Rebecca Poyourow said, "you demoralize the entire community and drive parents away."