Well what was Garrett expecting when Cabal saw him? The man's been trying to capture or kill Cabe for the past 40 or 50 years. Now that Garrett's standing in his living room can he blame the dhampir for trying to keep himself alive and free.
You'll note Garrett didn't do much to defend himself from Cabal's onslaught. Is that because of his continued illness or is it something else entirely? Guess we're going to have to see if he continues to allow the beat down or if he brings some defense to bear.