Congratulations on following a very healthy diet.
Also it seems you are taking your drugs very regularly.
Regarding the advice on eating idly at night , it may not affect you blood sugar badly but may cause bloating
and reflux in some persons. Please discuss with your doctor regarding the basis for discouraging it.
Your fasting blood sugar is near normal ,but post prandial need to be .reduced.
It can be achieved by increasing the morning insulin
Also tablets that delay absorption of sugar can be tried ( glucosidase inhibitor like voglibose
in low dose can also be tried.
Your doctor who has been treating your diabetes
for a long time will be in a better position to make the choice