Please take a look at this thread:
Galley Sink Drain Leak
There are 2 - methods for you to consider. Engineer Mike provided a detail explanation on how he would fix it. I just updated the thread with my ultimate fix. Regardless, it is a tight space in which to work and your 2007 cabinets are quite different than my '03 cabinets. Therefore, Engineer Mike's fix might be better suited to your coach since you both have closer model years.
If you're planning on fixing it yourself, I would suggest investigating the leak to the point of knowing exactly where it's broken and how you plan to work on it. I was able to start at the stand pipe and remove the original fittings along with 1/2 of the flexible PVC pipe. Mike's fix starts at the "break" point which could be dictated by how much access room you have. Good luck! It's doable but quite a PITA.