A long long time ago, I was a 20 year old store manager for a huge chain that specialises in glittery tat, scrunchies, cheap make up, and has it's ear piercing table in the window (need any more clues).
One of my weekend staff accused me of racism. My GM called a meeting with me to tell me. As I was vital to the operation of my store, and my accuser was contracted for 4 hours a week, it was she who didn't work for the 2 weeks it took for it to be confirmed to the GM (who didn't believe it in the first place) that I am not racist.
The stuff I had to respond to was insane - "One day there was just me (her) and her (me) in the shop. She took 1.5hr for her lunch break. Didn't offer me the same. Also she bought clothes and tried them on in the shop FOH!". Me - "One day we got paid. I had to change cash for a holiday, she needed to sort out her bank account. It was dead so I allowed us both an extra 15 mins on our lunch break. No I did not use the shop floor as a dressing room. I tried the clothes on in the staffroom."
All staff were interviewed, then it was dismissed. I was terrified but I knew I'd done nothing wrong. She came back to work, bought me a lovely present when it was my birthday, left for uni. On her return it was obv never discussed, it was like it never happened. I'll never forget it, and it always makes me think when I think I might have a whinge.
Sorry that doesn't help other than - I always knew what I could potentially be suspended for. As your friend should.