Is that mechanic famous or infamous? I dont know if the fuse box on your car is where it is on an S2, but on the S2 it is right where this guy will have been working. It is likely to be an easy problem to fix with a multimeter and some knowledge of the wiring, I'd have a bet that its not a fuse but some wire pulled off somewhere under the dash. However good he is, he should not be above offering to fix for you something that might be traced back to work he did.
Daily drive is a Giulia 2.0 MA, wife drives a 939 Spider in the summer and a Abarth 595 in the winter. For special sunny days we have a S2 Spider Junior in the garage.