I was able to replicate the scenario. You’re right, I tested with $200 and when ‘Send amounts’ is checked, DC options are returned by UPS. I reviewed the code and the API documentation and unfortunately there doesn’t seem to be anything I can do about it. The XML request is being sent WITHOUT DC request when ‘None’ is selected, which is correct. It’s still not being sent regardless of ‘Send Amounts’ being checked or not. UPS just insists on returning DC options if the package is insured and over a given value.
There is, however, a workaround for your case. You can modify the XML response from UPS however you like (like setting DC to N/A or removing it altogether) using the filter