I'm sorry, this really hurts. I'm super impressed by your positive attitude.
I would try with Kroger again. Here's the phone number 1-866-544-8062, option 2, I think. I would briefly explain your story again, because you are trying to distinguish yourself from gift card scammers. Having the activation receipt should go a long way with that. I have found Kroger customer service over the phone to be generally friendly, though I've never worked with the gift card team. Remember, never take a "no" answer from someone who doesn't have the authority to say yes.
I purchase my gift cards from Kroger online, as much as I can. I receive an email with the card number and pin/access code. I typically immediately redeem it into my AirBNB account. Once in my AirBNB acct, it can't be transferred to another AirBNB account, so that feels relatively safe. I know there are gc problems when purchased online, as well, but just wanted to offer it as another option.