An elf, some candy and HELP is needed

Bug and I headed over to the mall tonight- my goal was to get pictures with Santa before the holiday rush starts since I will be spending a week in Lisbon, Portugal (yes, you read that right) for work. Since I am losing a week of potential holiday activities with Bug, I figured I needed to start early.
Since all the stores are starting holiday sales early, I figured that the malls likely had brought Santa in early, but apparently I was wrongs since there were no Santas to be found.

As we were leaving the mall, I decided to walk Bug through the Bass Pro shop store- they have tents set up and Bug likes tents- he likes them a lot. We had never been in the downstairs section of the store and since Bug also wanted to see the fish (we could see them from upstairs), we headed down. WELL, guess who was sitting downstairs?????
SANTA- yes, Santa is at the bass Pro shop and has been since 10Nov. Who knew.
So bug walked over and then decided that maybe Santa was not so cool and perhaps momma should go with him- so we got our picture with Santa!!!! I walked over to pay for the picture- or at least choose the options and the picture was done (literally, 20 seconds) and there was no charge!!!!!! I think I have found my new Santa fix- it was a 5x7 photo- yes, we were excited. Oh- Santa gave Bug 2 small candy canes after Bug told him he wants a MOTO for Christmas (HEHEHEHE- i am so excited).

We wandered around for a little while and then I decided that we needed to leave so we could get home and I could make dinner. the drive home from the mall is about 20 minutes, so I gave Bug his 2 small candy canes. Well, 5 minutes from home, his little voice comes from the back seat saying "momma, my tummy doesn't feel good"- 10 seconds later the sound of retching comes from the back seat and it goes on and one.
Now I have 2 choices- stop the car and clean him up and continue home praying that it does not happen again, or I can drive straight home and clean everything up at one time. I choose the second choice and nearly regret since Bug emptied his stomach. I get home, park outside the garage so I have more room to open the car doors- not a pretty sight. I will say that Bug kept it all on him and in his carseat. I get him out and wiped down, send him into the house and then pull the car into the garage so I clean his carseat.

here is the help part- other than Resovle- what the heck should I use to clean the carseat. I have the car windows down, I cleaned up the carseat- including under the cover. I know that this weekend I will have to take the carseat out of the car 9no latch system, so I need the seat dry) and wah the car seat cover (involves taking the carseat apart).

The rest of our night has pretty much been focused on trips to the bathroom, but he is sleeping now. he has no fever, so I am assuming that he ate something that disagreed with him.

So help- what do I need to do for the carseat- because the temps are going to be in the teens tomorrow morning and it looks like for the next few days, so driving around with the car window open is not a good thing?