wallybird7 said, "Apparently this crew didn't."
That is an assertion not in evidence. How do you know the storm showed on their radar? Was their radar working? Was it employed properly?
By the time the problem appeared on their radar any escape from the storm would have required extreme deviations from their flight plan with no communications to DAKAR.
They did note it at that time and made a deviation towards an area that appeared less risky than plowing on straight ahead.
Now, one might argue that they should have called Atlantico about this. But apparently this happens so often the pilots simply noted the fact and plowed onwards. I wonder what would have happened had they tried to check in at the follow-on control site after DAKAR since their flight plan was not properly forwarded.
But the pesky detail stands - moving aside from the storm at the time they saw it would have required some serious course deviations. At the time they hit it the storm was a very wide solid band.