My SO's parents are coming to visit and will be arriving at JFK around 7am after a 20+ hour trip. They are elderly and we thought they would be more comfortable driving back with us (a 4 hour ride if there's no traffic jams) as opposed to connecting to another flight. They are arriving on TG so the latter option would involve getting their luggage, re-checking it into a domestic carrier, and flying to an airport which is still 1 hour away from us

We were thinking of driving into NYC on Monday, staying overnight at a hotel, and picking them up first thing in the morning. Originally we intended to stay at a JFK airport hotel, but they seem to be unsavory from what i have read here and rather expensive (~$200 for a 3 star hotel for our dates). The alternative is to stay with friends in Manhattan (and somehow find parking for our car!) then drive to JFK the next day at 6am.

My questions are:
Is the traffic horrendous from Manhattan to JFK at 6am on weekday mornings? Can we expect to get there within one hour? Is there an alternative that might work better?

Thanks for your advice!