The 33-year-old Parisian, who is black, was blocked from entering the carriage at the Richelieu-Drouot station before being pushed back onto the platform while the group sang racially charged songs.
The incident took place prior to the first leg of Chelsea's UEFA Champions League last 16 meeting with Paris Saint-Germain, which ended 1-1.
Chelsea have since suspended five fans for their actions and offered Souleymane an invitation to attend the return leg at Stamford Bridge next week.
Souleymane's lawyer Jim Michel-Gabriel confirmed on Friday that his client had declined the offer.
"He doesn't want to go to London to watch a football match because he's very shocked," he told Perform.
"It's too early and he's told me it's too early for him to go to London and to see the match.
"He doesn't want to see a football match at the moment. He doesn't want to go."
‘I won’t miss Match of the Day as that’s the person I am – I’ve never missed playing football, even though I loved it. The show will be fine – I’m thrilled to be leaving it in good health’ Gary Lineker tells FFT how he’s feeling about the end of an era
'It was agreed that I’d join Manchester United. So, imagine my surprise when I got off my flight south and heard a Cockney voice saying, "Welcome to Tottenham"': Rangers legend recalls transfer misunderstanding in signing for Spurs
