The decoy car should probably be taken from nearby, and so should not incur much noise penalty, and with the weather improved, there should be very little noise apart from distance. Running or not, a car should be on the matrix, so that should not be a barrier. Also, Chino will be your hands and feet if you need any anything shy of a direct connection. So far, no one has locksmith, so the B&E has to be through Hacking or Cybercombat. The DR of a car is such that there is no significant need for a DC and you can hit all of Aspen with less than a -3 to your DP due to distance. If the car is in a garage, you might experience another -1. Most vehicles are pilot rating 1-3 which should make them DR 1-3, or 2-3 if you use the table on pg 234. So, outside of a PAN, the highest dice pool you will face is 6, protected by a PAN you will add the DR of (max) 3 to a commlink of (max) 7 for 10 dice. Your DP of 15 - (max) 4 vs. (max) 10 still provides decent odds of success. You can choose softer targets, go hotsim, use edge, and/or use programs/agent teamwork to add more to your DP to improve your odds. You can grid hop in order to negate that penalty - in Aspen, it is unlikely that any vehicles will be on the public grid since anyone that can afford to come here can afford a lifestyle that provides them better Matrix access.
If they find us again and we don't have a car, our only option is to stay and fight. And if we survive, fight the next hit squad because we can't move fast enough to evade them on foot. So I think a vehicle is critical, unless I've overlooked something important.
I'm relatively new to the game, so I might be missing some important rule(s) that make stealing a car remotely more difficult than I've outlined, so I will have to defer to your expertise. My understanding of car theft isn't so much stealing it, as it is not getting caught once the owner notices it has gone missing.