But you can't, I tried before.. you can't jump out and it didn't even looked like you can roll.
Please try rolling. Like I said in my post, you'd be surprised how many times you can actually escape it by rolling. I'm actually still not completely convinced it's guaranteed because of how many times I've avoided it this way.
EDIT: And if it doesn't turn out to be avoidable, can it be changed so it is but create a mixup with downb? What I mean by this is if you know the opponent is going to roll, you can chase them with downb instead of doing sideb for a punish or something of the like. So essentially just making it a tick throw but with the ability to cover other options like rolling or jumping.
EDIT2: Also did everyone ignore the fact that FALCO of all people might have one of these guaranteed grabs on shield?