In any case (flying or driving) you most likely will run into issues (rebooking fee, no space on the next flight for 7 people....) if you don't show up on time at the CX counter.

Consider weather and check the on time record of your B6 flight.
Check https://www.flightradar24.com/data/flights/b6671
In the last week the flight was 4 hours late once, on time otherwise.

Estimate the likelihood of making it in time. Estimate the cost if you don't make it.

Personally I would drive the evening before and overnight at the airport, but I have been burned before in these kind of situations.