Hello ekamonv
Kindly note, there is an English-speaking SBB Community, too: SBB (EN) - SBB CFF FFS Community
To make it short: if you refer to the Mitfahrtageskarte / Carte journalière accompagnant/e / Carta giornaliera per accompagnatori, yes this is possible. The number of people travelling with a GA holder is not limited, provided everyone has their own ticket.
Kind regards,
Roland