He is on coalitionoftradefolk
If this isn't correct, will fix.
However, the only allakhazam information about the banker states he does attack players low with coalitionoftradefolk.
http://eqbeastiary.allakhazam.com/search.html?id=1058
About bankers attacking.. i know for certain the goblin banker in runnyeye would attack. On a related note, you can bank with bankers while fighting them.