I got a note on my Costco membership because my father-in-law bought something!

My 79-year-old father-in-law (who doesn't speak English) is visiting us. I took him with me on a Costco shopping trip (he is not a member, but my wife and I are). Once inside, I told him he was free to look around on his own if he wanted, and he agreed, saying he would wait for me at the food court when he got tired.

About 15 minutes later, I got a call from my wife saying he was in trouble at the checkout area! I rushed over and found him with what seemed to be the store manager, holding a backbag and its receipt. It turned out that my father-in-law wanted to make a purchase on his own, despite not being a member (yes, we had told him before that Costco is members-only). The employees didn't know how to communicate with him, so they just allowed the purchase and then called me over to explain to him that this shouldn't happen again.

I was very apologetic and took full responsibility for bringing him inside despite him not being a member. At first, the manager seemed understanding and only wanted to ensure it wouldn’t happen again. But then it seemed like he changed his mind and asked for my membership card so he could put a note in the system.

I fully cooperated, kept apologizing, and allowed the manager to add the note.

Now I’m worried and unsure what kind of note that was. Will it ever expire, or is it there forever? Will I get suspicious looks from the employees at the entrance, checkout, or when making a return (will the system show them some kind of flag)? Finally, should I have handled this in any different way?

ETA: I called the store this morning asking about the note, they told me it was a card sharing! After explaining the issue and that I haven’t shared my card with anyone, and the transaction was basically “cardless” they removed the note.