No doubt!! You have to consider several factors, and sometimes, taking a car is the best option. But as you say, it works out better when you have an entire family.

The OP only described one colleague who could have used the train on their own, rather than a single car for two passengers (one of which wasn’t part of the travel). I guess in the OPs case, you’d have to also consider whether they were being paid work hours for that drive.

So in this case, I think a train (assuming it was accessible and economical) would have been the better option for the OPs colleague. LOL