Bugged Recall / Hacker?

i saw what happened he had his shield up for a good bit of the channeling and since he was just about done channeling your e damage couldn't interrupt it since the only thing that stops a recall is taking hp damage

Not a hack or a bug, but a combination of the worst possible luck you could have.

There are two mechanics at play here.

1. Damage done to shields doesn't count as damage taken (you see this most frequently when you don't get an assist if you just popped a shield)
2. Damage taken in the last fraction of a second of a recall doesn't stop a recall

So your auto triggered the shield, your binding failed to break the shield, and you broke the shield too late for it to matter.

Now, the one thing that seems suspicious to me is that you can recall through a root, but it's likely recall is just treated like a channel instead of like a mobility spell. Just like your binding wouldn't stop a Nunu ult it didn't stop there recall without the damage going through.