please. go re-read the manga.
we have no idea how the 2nd hokage controlled his summons,
but orochimaru implanted a seal into their backs that gave him control.
so, its most likely thats how kabuto is using the jutsu.
when the souls are first summoned they retain their original minds and memories. (ex. when the 1st and 2nd talked to the 3rd)
but orochimaru's seal turned them into mindless puppets.
so it doesnt make kabuto better using the jutsu.
and Madara Uchiha hasnt been alive for 100 years for no reason.
he wasnt scared. that was just shock that this dude came to fight me and pulled out some heavy jutsu.
he's not gettin caught in a genjutsu by itachi, he's not getting touched by any other fighter there....
so what exactly does he have to be scared of?
he know exactly what every single one of those people can do cause they worked for him at one point. lol.
hes just shocked a lowly spy who sasori didnt really care about busted out the 2nd hokage's (who madara has fought. dont forget that.) jutsu.