Be advised, it is a suggestion. There is no hard evidence that okra, or okra water is beneficial in the treatment of diabetes. There is one suggestion that has been proven to be the best solution for a diabetic condition. See your doctor.
From Healthline –
Okra has long been favored as a food for the health-conscious. It contains potassium, vitamin B, vitamin C, folic acid, and calcium. It’s low in calories and has a high dietary fiber content. Recently, a new benefit of including okra in your diet is being considered. Okra has been suggested to help manage blood sugar in cases of type 1, type 2, and gestational diabetes.
Source: Benefits of Okra for Diabetes