I am not versed in Illinois contempt law, but judges have very broad constitutional authority to sanction people or companies for intentional failure to comply with a lawful order. In this case, you could expect the judge to do something like order the company to pay five thousand dollars per day until they disclose the records.
There could be an argument that the judge could legally order the sheriff to seize their servers or throw the CEO in jail until the company complies, but for some reason stuff like that doesn't seem to ever happen in the corporate context.