Sounds like she's making up stuff since you're at the bus stop with her. I'd make sure the bus driver is aware and see if she can sit right behind them.
I had a similar issue with my granddaughter. She'd refuse to get dressed even after picking out her clothes the night before all by herself.
I got tired of it. I'm a logical sort of person. I got tired of her doing her morning routine. I said we're leaving in 5 minutes, when time is up your going out the door in what ever you have on. Now we lived in a home that had a sheltered entry on the porch. No one can see us when we're standing outside our door, we had to take about 5 steps out for anyone on the street to see us.
I went to her room after 5 minutes and she wasn't dressed. I took her out the front door and put her on the porch and acted like I was following her out. I said "Get in the car!". She was hysterical of course, she wasn't even out of her PJ's.
I reminded her I had given her warning and told her 5 minutes or else. This was the "Or else". She begged to go in and get dressed. I told her she had 5 minutes to be back on the porch or she was literally going to school in what ever she had on.
She was back on the porch in less than 5 minutes with appropriate clothes on.
She has always been up and dressed on time. I know I made a harsh decision by putting her out the door without being dressed but she didn't think what I said mattered to her. I had to teach her to mind me and to believe that I was not to be disrespected and ignored.