Seems like it, though some details don’t exactly match, probably to conceal ‘Roger’ a bit. Research Brennan’s policy influence, background and behavior quirks. They sure match ‘Roger’.
And if Brennan isn’t Roger, I haven’t been able to identify another candidate.
Otherwise, the ‘Brennan is Muslim’ claim is just blogger speculation. It’s also possible Brennan did a fake conversion to gain the confidence of someone important.
While riding a bus to class at Fordham University, he saw an ad in The New York Times that said the CIA was recruiting, and felt a CIA career would be a good match for his "wanderlust" and his desire to do public service. He received a B.A. in political science from Fordham in 1977. His studies included a junior year abroad learning Arabic and taking Middle Eastern studies courses at the American University in Cairo. He also received a Master of Arts in government with a concentration in Middle Eastern studies from the University of Texas at Austin in 1980. He speaks Arabic fluently.
Brennan was Chief of Station in Riyadh in 1996.
I’ve read in other sources that he is a Muslim. I think it may even have been mentioned after 9/11, when they were busy trying to find “peaceful Muslims” to hold out as examples.