ElBaradei has no constituency of his own, no political base, no political history in Egypt at all. He has lived abroad for decades. He has less of a residency claim to Egypt than Rahm Emanuel has to Chicago. A man with no constituency allied with a highly organized and powerful political party is nothing but a figurehead, a useful idiot that the Brotherhood will dispense with when it ceases to need a cosmopolitan front man.
The Egyptian military, on the other hand, is the most stable and important institution in the country. It is Western-oriented, and rightly suspicious of the Brotherhood. And it is widely respected, carrying the prestige of the 1952 “Free Officers Movement” that overthrew the monarchy, and the 1973 October War that restored Egyptian pride along with the Sinai.