I think everyone might do the insurance cost differently, but I would do just as you've described 190*(3/7). Regarding the issue of insurance costs in the calculator, I'm not quite sure I follow you. It could be an error in the sheet, but essentially all insurance costs for both parents are added to the overall support amount. Then each parent is responsible for their Income Proportionate Share (IPS). Then after the IPS is calculated, the actual payment for things like insurance is credited back. Long story short, each parent ends up paying their own IPS of the insurance. It should work like that anyway.
This is not shared custody right? Your husband has parenting time, but is not the primary residential parent?