Unlikely I'd say. In c. XIX Bolivia wasn't a threat for Brazil, even Chile when they were fully mobilized during the War of the Pacific,
had problems in peruvian sierra due to attacks from montoneras (indigenous and peruvian troops). Bolivian montoneras wont make it easy for Brazil. They first need to build enough infrastructure to supply their troops across the pantanales and the rainforest, then mobilize them for hundreds of kilometers just to face fierce montonera resistance in the arid altiplano over 4000 meters above sea level and even if they win, they'll need to build more infrastructure to connect their new territory with the rest of the country because Bolivia hasn't infrastructure at all.
The very first railways were built in the Atacama coast by private Anglo-Chilean Company of Salitre and Ferrocarril de Antofagasta. Would Brazil have enough resources to do that? Even if they do; Argentina, Peru and maybe Chile will not like the idea of an expansionist Brazil and alliances and treaties might be signed. It's just too risky and unlikely.