Mechanics and Fixing Any Questions Answered

Is this banjo part attached to the cable at factory then?

Yeah, what are you actually trying to do again? If you want to reuse that hose on a deore you can just cut off the banjo and use a suitable olive and barb assuming the hose is long enough, can't really go the other way without an aftermarket banjo, I think jagwire make one, you also might have the "wrong" hose, those slx use bh90 and older deore use bh59 which have a slightly different bore, in practice again they'll work OK though if you have the right barbs.