Its possible she had a good reason (in her mind) for cancelling (Maybe she woke up with a giant pimple in her face or whatever). If she doesnt counter-offer (believe it or not, not every woman on earth is aware she is supposed to counter-offer) I would just pretend to believe what she said and give her the smallest "in" to pick this up another time.
In your example, maybe something like "Emergencies can be a b1tch. Let me know when your friend is out of the woods". If you dont hear back from her, you know what´s up.
Ok kids, gather around. Its story time:
Years ago, my woman thought she had Covid and she cancelled what was supposed to be our first date. We were supposed to go out saturday and she cancelled in the morning via text, saying she needed to rest during the weekend and take the test on Monday.
She wasnt aware she was supposed to counter-offer. I though it was possible she had low interest and making it up. I could have blocked her and / or delete her. I figure there was a possibility she was telling the truth and just said something like "Rest and get better soon. Let me know the test result" and forgot about it.
Next monday I got a text from her: "I tested negative for Covid". Had I blocked her or delete her, my life would be completely different right now.