If the lower control arm bushings are deteriorated and sloppy then the dynamic load of braking will throw the static alingment settings off and could cause a pull, but if you have actual numbers from a recent alignment, posting them will help in analysing the situation.
Absent of abnormal noise, wheel bearing condition can only be determined by removing and cleaning them followed by a thorough inspection. If okay, repack, install with new seals and set the clearance properly.
I don't think Mercedes has a front wheel bearing service interval for your model, but if over 120K miles, it's not a bad idea to do an inspection and repack.
The other issue could be tires. Swap the front tires side to side to see if the problem is the same. If so, it's probably not the tires.