Update: Since the key replacement we have had a handful of no crank situations, where key turns all the way but no crank... usually starts after a second attempt, but today it took 3 attempts before starting on the fourth. Not sure what this indicates and so far my calls to the dealership it sounds like they would just want to throw parts at it, not my style of diagnosing things, not sure of the competency of mb techs. Going to go have codes read on Wednesday.