I think something must changed since you did it. now I have 3 really well equipped rangers. I spent lots of gold for their mostly legendary stuff. and situation is same. maybe a bit better. but just a bit. its only about luck, to wait till last fight will be single + boss (not 4+boss), as 2nd posibility written in haroda description. nothing else.
and I`m still think its pretty nasty, make it almost not possible to do it, without luck.