If you haven't already understood, let me explain.
Ghana sees very high levels of real fraud. False documents, eDVs filled in incorrectly by agents (and selectees trying to lie or create documents to match the story), fake marriages. You name it - the Ghana embassy sees it. This should not be a surprise to you or anyone else in Ghana. And to others I say please let's not have some nationalistic, childish reaction (as I have had from some Ghanaian's previously) to the truth I am saying. This means that refusals in Ghana are going to be high.
Now - that is what the COs in Accra are dealing with on a daily basis. Their reaction to that reality seems to have been a swing in the other direction. They are extremely sensitive to small errors, they are very picky (even dismissive) about genuine documents and they are even administering oral tests to confirm stated education (against guidelines). If they see one or two small errors they assume some sort of fraud even in cases which I believe are genuine. They end up refusing cases incorrectly. The combination of accurate and inaccurate refusals means the chance of approval in Accra is low. Very low.
For a case to be approved in Ghana your eDV should have been accurate. Your preparation needs to be excellent. Your documents need to be genuine. Your education needs to be well documented. Above all, you must be genuine - they have seen many liars, and have I am sure quite expert at identifying liars.