"That came as a shock to us," said Maricela Torres, the new Glendale Bears president.
Marquez was allegedly employed while she was receiving disability checks, according to court documents.
The fraud, which allegedly occurred from Sept. 3, 2005, to Dec. 30, 2007, was discovered after an investigator noticed a discrepancy between Marquez's wage reports and disability claims, according to a criminal complaint.
Marquez pleaded not guilty last week to 23 counts of insurance fraud, grand theft, identity theft, forgery and petty theft with priors, said Shiara Dávila-Morales, a spokeswoman for the Los Angeles County district attorney's office.
Marquez already has three grand theft convictions, which occurred in 1993, 2000 and 2005, according to a criminal complaint.
If convicted of the charges, she faces up to 20 years in state prison, said Deputy Dist. Atty. Hyman Sisman, who investigates health-care-fraud cases.
Attorney Mearl Lottman, who represented Marquez during her initial court appearances, said her case was complex, and has since passed it on to another public defender.
Marquez has remained in police custody without bail because she is considered a flight risk and might use some of the funding acquired through the alleged fraud to pay for her release, according to court documents.
The Glendale Bears board of directors removed Marquez from the top position after they alleged that she changed banks and made decisions without consulting the board, failed to pay past debts or provide proper safety equipment for players and didn't pay fees to play in the San Gabriel Valley Jr. All-American Football Conference.
Board members also alleged that they were never shown financial records. And when Marquez finally turned them over, they were unclear and incomplete.
The organization's board has since turned over financial records and documents to Glendale Police Department detectives for investigation, Torres said.
Under Marquez's leadership, the organization's former treasurer, Louella Lucas Ragland, embezzled more than $30,000 in July 2008.
Ragland was convicted of embezzlement and ordered to serve three years' probation and refund the stolen money.
While Marquez remained at the helm, she said the theft had left the organization $15,000 in debt.