tourist visa to US

Hi
slightly curious situation here

my daughter (now 16) is British.
She emigrated from France to the US in August 2015 on an F2 visa. her mother was studying at USCLA on an F1 visa.
The F1 visa was valid from 2015 to 2020.
her mother finished her course in 2017 and then carried on working in a degree-related role until July 2018. In Jan 2018 she applied for an O Visa and was denied in July. I do not have the exact denial letter nor the reasons. I recognise that this is important. Impossible to obtain.

My daughter wishes to return to the US for 6 weeks to visit her friends. She has been told by the US immigration attorney that she could state on her esta form that she has not been denied a visa, but she would likely to be rejected at the border. How helpful.

In filling in the tourist visa application form my daughter is faced with the question about visa expiry and visits to the US. Her current visa expires in 2020, but stating that is not an option.

any advice please? she only wants to go and say goodbye to all her friends and previous life there! Can it really be this difficult?

thanks
Justin