I'm certainly no expert in the law in this kind of thing, but I can't imagine you could be held responsible for this debt. It's the companies debt, not yours and as long as you weren't an owner of the company I can't see how the debt is yours.
I may be wrong about this, but I don't think a collection agency actually has any legal authority. I think their job is to put as much pressure as they can on you to pay in an effort to make you nervous about what can happen, but I don't think they can actually force you to pay without going to court. And I'm not sure how much they'd be willing to go to court for $350.
Someone please correct me if I'm wrong about this. What I'm saying is my opionion based on what seems like common sense, but I know the law doesn't always work from common sense.
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