Betweenness centrality measurement ignoring inverse paths?
The algorithm that you have mentioned here is definitely correct. You can refer to the correctness proof in the paper.

This algorithm is implemented in many libraries and ready to be used including NetworkX, Boost, GraphStream, and MATLAB (3rd party I guess) and many others. Also, many other people (including myself) and companies have employed the same algorithm.

If you are getting unexpected results, please revise your implementation.