Hello, I will agree that the odds of suspention failure the day after brake work would be rare. It is possible the sensor arm came off when lifted or overextended when lifted preventing the system from working correctly. There are 3 fuses that feed the system which are :
AC
Hazzards
BTN
The BTN would have to be ok or you would be missing many other items from working. Isuspect fuses ok as the light does come on. I have seen on some vehicles when lifted, the air shocks hag so much that they start to leak once back on the ground. if the original shop can not figure th problem out, yes, 100% get a second opinion and have them be sure to recheck the height sensor. I feel a suggestion to replace the whole system to manual at this piont is not practical.
I do agree in that i suspect? the shop bumped something etc. it is possible but i can in no way confirm. You can look around compressor yourself to see if any plug disconnected etc. Some shops are just not comfortable with auto ride suspection problems. If the original shop can not locate the problem, then i would notify them you will get second opinion. just keep in mind it could ? have failed day after repairs but would be very odd to do so. This air ride system was very reliable and i have done little in any repairs to this type system. I am leaning towards a shop error. Most all of us techs have had a minor problem from time to time. it can not be ruled out
ASE Certified Technician
32 years Foreign / Domestic Cars All aspects of Diag and Repair