New Vestalink customer here too. I had this issue with GV not recognizing my button presses, and the above resolution works.
However, it didn't work at first. I had to completely reset the Obi to get it to work. I removed the Obi 202 from my account, reset it to factory default, added it back to my account, and then added Vestalink and made the "InBand" change. NOW it works!
So just a heads up for anybody else that has this problem. The above solution will work, but if it doesn't, you might have to go the extra mile by resetting it to completely clean out the old GV settings.