Google Sheet -> Calendar -- Create Events with CalID

I have a giant spreadsheet to create student schedules. I've summarized all of the event information in one tab (see screenshot). The current Script I'm using creates a NEW calendar with the events. I just want it to add the events to an already pre-created calendar.

enter image description here

/**
 * Creates a Google Calendar with events for each conference session in the
 * spreadsheet, then writes the event IDs to the spreadsheet for future use.
 * @param {Array<string[]>} values Cell values for the spreadsheet range.
 * @param {Range} range A spreadsheet range that contains conference data.
 */
function setUpCalendar_(values, range) {
  let cal = CalendarApp.createCalendar('Conference Calendar 2');
  // Start at 1 to skip the header row.
  for (let i = 1; i < values.length; i++) {
    let session = values[i];
    let title = session[0];
    let start = joinDateAndTime_(session[1], session[3]);
    let end = joinDateAndTime_(session[1], session[4]);
    let options = {location: session[5], sendInvites: true};
    let event = cal.createEvent(title, start, end, options)
        .setGuestsCanSeeGuests(false);
    session[6] = event.getId();
  }
  range.setValues(values);

  // Stores the ID for the Calendar, which is needed to retrieve events by ID.
  let scriptProperties = PropertiesService.getScriptProperties();
  scriptProperties.setProperty('calId', cal.getId());
}


/**
 * Creates a single Date object from separate date and time cells.
 *
 * @param {Date} date A Date object from which to extract the date.
 * @param {Date} time A Date object from which to extract the time.
 * @return {Date} A Date object representing the combined date and time.
 */
function joinDateAndTime_(date, time) {
  date = new Date(date);
  date.setHours(time.getHours());
  date.setMinutes(time.getMinutes());
  return date;
}