Yes, the issue is very likely that the 941 form requires a QuickBooks program patch/update, but nowhere is that mentioned in the payroll updates nor are you notified when you run the form that the data sent from QB to the form is in an old format that is no longer sufficient for the form.
Both of these things, to tell customers to update QuickBooks, and to warn them if they don't, could have been implemented by Intuit - the mechanisms exist and they've done it before - but they didn't this time.
To make the form work, update/patch QuickBooks to the latest release from the help menu and then restart to apply the patch.