SABMiller PLC rejected a takeover proposal from Anheuser-Busch InBev NV on Wednesday that esteemed it as high as £68.24 billion ($103.88 billion), the most recent salvo in what is rapidly turning into a strained negotiation between the world’s No. 1 and No. 2 brewers. The strains stretch out to SABMiller’s two largest shareholders, U.S. tobacco company Altria Group Inc. what’s more, the Santo Domingo group of Colombia. Altria, which holds a stake of more than 25%, said it would bolster a deal at or above AB InBev’s proposed price. The Santo Domingos’ BevCo Ltd. venture vehicle, with around 15%, joined…