I have come to the conclusion that Intuit seriously dislikes customers that are concerned about security and truly understand software and risks.
This thread is a testament to that.
I was already using Quicken when Intuit developed the first version of Quickbooks in1998.
I switched all corp accounts to Quickbooks because of time tracking and invoicing. It was great. As prices increased, support and security decreased in my opinion. 

Two potential work-arounds.
1) Build a VM with an older version of Windows and Quickbooks Desktop - do NOT connect this VM to the internet - no browsers - no email connectons. Nothing to invite or accidentally create an intrusion.
You must protect access to this VM! You will need to make changes to the registry depending upon the version you go to, a professional will be able to make those changes. If you do not know how to do this hire someone you trust! 

You may need to rebuild your company - or company files, but we are coming to year end - so closing and starting fresh may not be the same level of headache as later. Just make sure you have backups of reports and other important historical data.

2) Switch to Quicken  - they are no longer a part of INTUIT. The interface and reporting function is a bit clunky from Quickbooks Desktop, but your data is your data.  You can, if you choose, integrate with online banks and investment accounts.