The key to curing dyslexia is usually very simple. You just need to understand why the person is struggling to read.
Being diagnosed as dyslexic just means that you have "specific learning difficulties with reading, despite normal intelligence". It does not give any information on what is causing the difficulties with reading.
I get a bit frustrated about it because it is the equivalent of a mechanic telling you your car has broken down. What you want to know is why it isn't working and how to fix it!
Well, the good news is that there are just a handful of reasons for dyslexia and quite simple cures to most of them.
Furthermore, 80% of dyslexia is caused by an "auditory deficit". This means that the person reading is not using their auditory brain cortex in order to read. They are using a purely visual approach, effectively viewing a word as a picture to be recognised.
Another 15% show signs of dyspraxia, which is caused by inefficient signal processing in the cerebellum. That can also be helped quickly and easily.
So, don't accept a diagnosis of just dyslexia. Demand to know what is causing the dyslexia and you will then be just one step away from a cure.