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."
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