While antibodies are typically present in type 1 diabetes, they are not always. There can be antibody negative type 1.
Further, there are currently about 5 different known possible antibodies that can be tested for..... so testing only 1 or 2 of these is not conclusive.
Did they test c-peptide and insulin levels (together with the blood sugar levels?). Also, did you try type 2 drugs, and did they work?
There are many different types of Mody already identified, and surely more to be discovered. Some of these need insulin early and some do not / respond to oral meds. The testing for MODY is still early days, and given the cost may not be worth your while, unless covered by insurance. In my case, I suspect Mody, but testing is not an option at this time..... so I just live with the not knowing for sure, and focus instead of managing this very well.
Bottom line, is that your diabetes needs to be well managed to ensure a long and healthy life for you.
The best way to do this, in my experience, is low carb diet, exercise, weight management, and appropriate meds.
If you are not able to achieve normal blood sugars (ideally hba1c close to 5, and target FBS < 95, and post eating less than 140, though ideally < 120 or even close to fasting levels), then you may need to be using insulin.
Are you using insulin? How are you going?
Please let us know.