Yes, that is the common usage, but it is none the less inaccurate.
Usage determines the meaning of words. You can insist, for example, that ‘gay’ means ‘light hearted, festive and and happy.’ But after asking directions to the nearest gay bar, you can’t blame language for the wretched experience that awaits.
Use your own search engine. Read as many definitions of ‘brokered convention’ as you like. Most if not all agree with Bing, bc that is the current usage.