As the title suggests, I am wondering if it is possible for multiple respondents (lets say up to 50 people) to simultaneously do the survey using the same token?

Same token with or without token answer persistance ?
manual.limesurvey.org/Participant_settin...response_persistence

With : no because each user will overwrite the previous answers during the movements in the survey
Without : yes, no issue. But you need to set use left to 50 or to allow multiple reponse