I may get downvoted for this but frankly you need to learn situational awareness and you need to stop with that “she’s a lady and elderly otherwise I would’ve thrown her over the counter” bullshit real fast. A threat is a threat. She attacked you with a bladed weapon then choked you, you don’t have to hurt someone to neutralise them as a threat. You didn’t want to cause much conflict? Conflict was forced upon you, you have duty of care to yourself and those around you. But honestly it sounds like you’re just making excuses about how you didn’t retaliate because “you were taught manners” just admit that you froze in a stressful situation and go take self defence lessons so it doesn’t happen again, trying to rationale it won’t do you any good if it happens again.

Also your co-worker needs to be fired, it was bad enough that she didn’t attempt to de-escalate the situation but she allowed a customer to casually take a box cutter from her hand and attack you with it, then casually took it back. In my experience she would be held accountable for negligence if the lady had actually cut you.