I need to think about that. The sun and planets pretty much have poles aligned. The planets do not point a magnetic pole at the sun, but in the same direction as the sun. Magnetic fields like to align, not go perpendicular to large fields. Also, I thought that not even light can escape black holes so why gamma rays? I need to look more into that theory.
Gamma rays are emitted by the accretion disc as material falls into the gravity well. It happens on the universe side of the event horizon, so it can still get out. Needless to say only the really high-energy ones get out.
Ultra long gamma ray burst caused by collapse of blue giant stars at he core of the Milky Way