Mr. B. Hat,
Every year we travel to LM station at about 5:30/6:00pm. The traffic is not too bad, but this might be a little late for your man. It usually takes about 15mins. If it's not too late for him I'd be happy to give him a lift, mind you there won't be much, if any, luggage room.
Travel to Paris for an in-laws wedding anniversary?! That's a bit tenuous isn't it? The man must be keen, I'm not even sure I can name my in-laws...
H