You're trying hard

I absolutely know you are, and how frustrating this must be for you - every aspect.
I've never had a C Peptide test myself and I'm not a doctor or a scientist, so all I can do is give you my opinion as a layperson with Type 1. When I was first diagnosed, I was upset and the surgery got an older Type 1 to phone me. She'd been diagnosed three years. She told me that she went through phases of having hypos just before lunch for no reason and I was to,watch out for this. She had had a C Peptide test and it showed she was still making some imsulin of her own, even three years after diagnosis. She was diagnosed as a young adult and was told that Type 1 comes on slower the older you are (ie slower than in children).
So that could be what's happening to,you. I've also read that some people still have some functioning islets many years after diagnosis. So - you can be Type 1 and still have some insulin production of your own. In addition, I've read that Type 1 is not solely a 'lack of insulin' - it's a disruption to that whole endocrine system. In simple words - the system that controls your blood sugar is totally messed up.
You said you were low carbing and yet your BS was so high the meter couldn't read it. So, to my unprofessional mind, that shows only too clearly that you need insulin. Online there is information that says DKA can take varying lengths of time to develop in those with Type 1 who don't take their insulin. This can vary from a day or so to a few weeks. But whether DKA develops quickly or slowly, high blood sugar is causing damage in the meantime.
I know you hope that your diagnosis may be wrong. You're not alone. I'm sure most Type 1s dream and hope that too. But accepting Type 1 means you can get on with your life. It doesn't mean liking it. I hate Type 1, but I accept I have it and I deal with it because I want to stay healthy.
Best wishes as always
@nessa1970 X