[mothered]

I was still in the process of attempting to get a refund for the most recent order (which I DNA’d) when they closed the account.

You've breached their terms, so given the account on which the Investigation took place Is closed for that very reason, It's unlikely they'll process a refund.

That being said, It won't hurt to call them and ask where your claim stands. Knowing Amazon's lack of common sense, you may get a representative who'll keep the claim active.