It sounds to me like you are on a really positive new wave of learning in diabetes care, which I am sure is going to serve you well. EllieM above, has given some really helpful advice on insulin & carb counting. And your knowledge around carb counting will only get better via the DAFNE course. On the last course I attended, I really appreciated being given some guidelines for estimating carb content by looking at the plate and when you haven't been able to pre-weigh everything. And I am guessing, for you, when someone else has been cooking, that this is the sort of thing that may really help. So if it is not covered off on your course, make sure you ask the question.
I do very much understand the fear of hypos. I had some rather extreme hypo situations in my adult life when I was transferred onto Lantus from my previous basal insulin. After a few months I was fortunately temporarily then shifted onto Tresiba, which was more reliable for me, until I could be put onto a pump with Novorapid, which is an insulin I know how I react to as I have taken it for the majority of my adult life. At the time, I had to invest in a private diabetic consultant who tracked my response to Lantus, which for some reason, in my body had an absorption rate that didn't at all coincide with what the drug company advised it should be. So relieved that this is now all resolved, because, like you say, those extreme hypo memories can persist!.
Are you taking regular blood sugar tests at the moment, pre-DAFNE, so you can get an idea if your blood sugar is sitting closer to the zone you need it to be in for your surgery to go ahead?. If you are & your blood sugar was higher than it should be, the conversion rate that EllieM gives you above is usually the starting point to correct it with your Humalog insulin - so one extra unit of Humalog for every 2mmol you want to reduce your blood sugar by.
Best of luck with it all.