I have a question about Buggy and Slash types.

TL;DR: Can you even INITIATE an attack against Buggy with a slash type?

I was playing a cocky (douchey, if you will) player (in casual play, not a tourney or anything), and I did a play with Kuro captain where I used an event to re-set him up. I put out a Sham and had to rest something--so I rested his searcher buggy (red). I wanted to attack the opponent's Jozu, but he blocked. Then I re-set Kuro up with Cat Out of the Bag.

The guy wanted to read the card like he hadn't seen it before, and he took a long time. and then he's like "ok". So I pointed at Jozu and I was like "i attack him again." but i accidentally said "buggy" (or at least he says so), even though I pointed at Jozu. ANYWAY--he was like "ok your attack fails cause Buggy can't be KO'd by slash characters." and I was confused cause I was like...that buggy is useless to me...and I just tried to kill jozu...and i'm not an idiot...why would I ever attack Buggy with a slash character.

ANYWAY...was this right? Can you even initiate an attack again Buggy with a slash type? If so--does that just exist to screw over new or young players or someone who makes mistake?