chucks

I had my rear axle housing leak fixed for the second time on my 04. Before I got home from the dealership the ABS and Traction Control lights came on. I turned around and took the car back. When I told them what happened the write up girl and service manger said they did not think it was anything the tech did wrong but they would check it out. I am thinking no way this had nothing to do with the repair they did. What do you guys think he could have screwed up to make ABS and traction control lights to come on. The car has 28,000 miles on it. Thanks for any info. I want some info to back up my thought that it was caused by the tech.