DeWitt said Thursday that the team was still investigating the matter but said no more than a handful of individuals in an operation that numbers in the hundreds -- describing it as a "needle in a haystack" -- were responsible.
A Houston Chronicle report revealed Thursday that the Cardinals had unauthorized access to Astros information as early as 2012, a year earlier than was previously known.
The extent of the Cardinals' reach inside the Astros' organization isn't yet fully known but was not limited to one or two occasions, a Chronicle source familiar with the details of the investigation said. The Chronicle previously confirmed two breaches into the Astros' system -- one in 2013 and one in March 2014. The FBI began its investigation after the 2014 breach.
"I still don't know the reason for it," DeWitt said. "I can't come up with a reason for it. It goes against everything we stand for. We don't know who did what here."
DeWitt and general manager John Mozeliak met with media at Busch Stadium a day after an attorney hired by the team said high-level executives were not involved in the scandal.
Both teams have said they are cooperating with authorities.
"We're committed to getting this resolved, we hope sooner rather than later," DeWitt said. "We're a little bit at the government's pace. We're not in a position of pushing them, as you might imagine."
DeWitt said he met with team employees Thursday and told them, "We've all been tainted," by the scandal and added, "It's a shame."
He said he had "zero knowledge" of the hacking before being informed by FBI investigators early this year. He said the team hired a law firm to "tell us how to act."
"You can imagine how shocked I was to learn that the FBI was investigating a potential breach ... because it didn't make any sense," DeWitt said.
He predicted the organization will emerge "stronger than ever."
"Those responsible will be held accountable," DeWitt said, "and we will continue what we feel is a great franchise."
Both DeWitt and Mozeliak said vengeance toward former Cardinals executive Jeff Luhnow, now the Astros' GM, should not have been a factor in the alleged hacking. Both attended Luhnow's wedding in 2012.
"I felt like we had a very solid relationship, a very positive working relationship," Mozeliak said. "When he did have that opportunity to go to Houston, I can tell you both Bill and I were advocates for him to get that opportunity and gave glowing reports."
Luhnow said the notion that poor password protection was to blame for the computer hack was "absolutely false."
Information from The Associated Press was used in this report.