Smelly damp car

BF accidentally left his car window down for a week and we had pouring down rain several days in a row while he was gone. (He drives a company car for work and just leaves his parked while he's gone)

He took the car somewhere and had the carpets cleaned, but it still smelled. And the carpets didn't dry for 2+ days and there was still pollen in the carpet. So we got some carpet cleaner and went over it ourselves, let that dry and vacuumed it. But it was still smelly.

So I got baking soda and sprinkled it all over everything. I think that got all the moisture out and the car smells a little bit better, but still not great. We vacuumed it again, but weren't able to get all the baking soda up out of the carpet. (oops)

He's hung an air freshener and fabreezed the whole car, but that just kind of masks over the smelliness.

Does anyone have any suggestions on how to get it smelling better?

You could rent a dehumidifier and let it work its magic in the car for a couple of hours.  Depending on where you live and your electrical outlet situation, you might have to get a long extension cord...or it might not even be possible if you live on a high floor.  Anyway, just thought I'd mention it.

Thanks!

We park on the street and it's kind of far away from the house, so I don't think that would work. (We've been going to car washes to use the vacuum on it.)

Maybe try putting a bowl of (unused) ground coffee in the car somewhere. A few weeks ago I didn't hear a timer go off while making stock and had burned chicken bones all through my house. I tried *everything* and liked the coffee the best because not only does it absorb the odor, it smells pretty nice while doing so.

Best of luck!

Same thing happened to my car last year.  I managed to treat it with bicarb of soda and shake "n" vac left overnight and vacuumed up in the morning.  I also bought new car mats as the stench really stuck in them and also when driving i would put the heat on full blast to dry the car out - it was so hot I had eyes like dried apricots! but it did eventually get rid of the smell - I also Fabreezed the seat with the antibacterial stuff

No suggestions to add to the above good ones but I just wanted to say how lucky he was to still have a car!  After a week parked on the street with windows open in the weather its surprising the car wasn't stolen or vandalised. 
I hope you get it sorted.  Musty cars are no fun to drive.